diff --git a/how-to-backup-and-encrypt-data-using-rsync-and-veracrypt-on-macos/README.md b/how-to-backup-and-encrypt-data-using-rsync-and-veracrypt-on-macos/README.md
index d7cffa4..dc2329a 100644
--- a/how-to-backup-and-encrypt-data-using-rsync-and-veracrypt-on-macos/README.md
+++ b/how-to-backup-and-encrypt-data-using-rsync-and-veracrypt-on-macos/README.md
@@ -265,8 +265,8 @@ cat << EOF > /usr/local/bin/check.sh
 
 set -e
 
-red=$'\e[1;31m'
-nc=$'\e[0m'
+red=\$(tput setaf 1)
+normal=\$(tput sgr0)
 
 printf "Backup hash: "
 
@@ -275,7 +275,7 @@ read -r previous
 current=\$(openssl dgst -sha512 "$BACKUP_VOLUME_PATH")
 
 if [ "\$current" != "\$previous" ]; then
-  printf "\${red}%s\${nc}\n" "Integrity check failed"
+  printf "\$red%s\$normal\n" "Integrity check failed"
   exit 1
 fi
 
diff --git a/how-to-clean-uninstall-macos-apps-using-appcleaner-open-source-alternative/README.md b/how-to-clean-uninstall-macos-apps-using-appcleaner-open-source-alternative/README.md
index 073ed9d..ce53ba9 100644
--- a/how-to-clean-uninstall-macos-apps-using-appcleaner-open-source-alternative/README.md
+++ b/how-to-clean-uninstall-macos-apps-using-appcleaner-open-source-alternative/README.md
@@ -18,7 +18,7 @@ Listed: true
 
 ```shell
 sudo mkdir -p /usr/local/bin
-sudo chown ${USER}:admin /usr/local/bin
+sudo chown ${USER}:staff /usr/local/bin
 ```
 
 ### Step 2: download [app-cleaner.sh](./app-cleaner.sh) ([PGP signature](./app-cleaner.sh.sig), [PGP public key](https://sunknudsen.com/sunknudsen.asc))
@@ -36,13 +36,13 @@ chmod +x /usr/local/bin/app-cleaner.sh
 
 ```console
 $ app-cleaner.sh /Applications/AppCleaner.app
-Checking for running processes...
-Finding application data...
+Checking for running processes…
+Finding application data…
 /Applications/AppCleaner.app
 /Users/sunknudsen/Library/Preferences/net.freemacsoft.AppCleaner.plist
 /Users/sunknudsen/Library/Saved Application State/net.freemacsoft.AppCleaner.savedState
 Move application data to trash (y or n)? y
-Moving application data to trash...
+Moving application data to trash…
 Done
 ```
 
diff --git a/how-to-clean-uninstall-macos-apps-using-appcleaner-open-source-alternative/app-cleaner.sh b/how-to-clean-uninstall-macos-apps-using-appcleaner-open-source-alternative/app-cleaner.sh
index 3927290..b2f5e70 100755
--- a/how-to-clean-uninstall-macos-apps-using-appcleaner-open-source-alternative/app-cleaner.sh
+++ b/how-to-clean-uninstall-macos-apps-using-appcleaner-open-source-alternative/app-cleaner.sh
@@ -7,8 +7,8 @@ fi
 
 IFS=$'\n'
 
-red=$'\e[1;31m'
-nc=$'\e[0m'
+red=$(tput setaf 1)
+normal=$(tput sgr0)
 
 if [ ! -e "$1/Contents/Info.plist" ]; then
   printf "%s\n" "Cannot find app plist"
@@ -31,7 +31,7 @@ processes=($(pgrep -afil "$app_name" | grep -v "app-cleaner.sh"))
 
 if [ ${#processes[@]} -gt 0 ]; then
   printf "%s\n" "${processes[@]}"
-  printf "${red}%s${nc}" "Kill running processes (y or n)? "
+  printf "$red%s$normal" "Kill running processes (y or n)? "
   read -r answer
   if [ "$answer" = "y" ]; then
     printf "%s\n" "Killing running processes…"
@@ -113,7 +113,7 @@ paths=($(printf "%s\n" "${paths[@]}" | sort -u));
 
 printf "%s\n" "${paths[@]}"
 
-printf "${red}%s${nc}" "Move app data to trash (y or n)? "
+printf "$red%s$normal" "Move app data to trash (y or n)? "
 read -r answer
 if [ "$answer" = "y" ]; then
   printf "%s\n" "Moving app data to trash…"
diff --git a/how-to-configure-self-hosted-vpn-kill-switch-using-pf-firewall-on-macos/README.md b/how-to-configure-self-hosted-vpn-kill-switch-using-pf-firewall-on-macos/README.md
index 8d7408a..8e29945 100644
--- a/how-to-configure-self-hosted-vpn-kill-switch-using-pf-firewall-on-macos/README.md
+++ b/how-to-configure-self-hosted-vpn-kill-switch-using-pf-firewall-on-macos/README.md
@@ -256,7 +256,7 @@ sudo pfctl -F all -f /etc/pf.conf
 
 ```shell
 sudo mkdir -p /usr/local/sbin
-sudo chown $USER:admin /usr/local/sbin
+sudo chown ${USER}:admin /usr/local/sbin
 ```
 
 ### Step 11: source `/usr/local/sbin` folder
@@ -294,8 +294,8 @@ if [ "$(id -u)" != "0" ]; then
   exit 1
 fi
 
-green=$'\e[1;32m'
-nc=$'\e[0m'
+green=$(tput setaf 2)
+normal=$(tput sgr0)
 
 # /usr/libexec/ApplicationFirewall/socketfilterfw --blockapp /Applications/1Password\ 7.app
 # /usr/libexec/ApplicationFirewall/socketfilterfw --blockapp /usr/local/Cellar/squid/4.8/sbin/squid
@@ -309,7 +309,7 @@ printf "\n"
 
 pfctl -F all -f /etc/pf.conf
 
-printf "\n${green}%s${nc}\n" "Strict mode enabled"
+printf "\n$green%s$normal\n" "Strict mode enabled"
 EOF
 chmod +x /usr/local/sbin/strict.sh
 ```
@@ -335,8 +335,8 @@ function disable()
 
 trap disable INT
 
-red=$'\e[1;31m'
-nc=$'\e[0m'
+red=$(tput setaf 1)
+normal=$(tput sgr0)
 
 # /usr/libexec/ApplicationFirewall/socketfilterfw --unblockapp /Applications/1Password\ 7.app
 # /usr/libexec/ApplicationFirewall/socketfilterfw --unblockapp /usr/local/Cellar/squid/4.8/sbin/squid
@@ -350,7 +350,7 @@ printf "\n"
 
 pfctl -F all -f /etc/pf.conf
 
-printf "\n${red}%s${nc}\n\n" "Trusted mode enabled (press ctrl+c to disable)"
+printf "\n$red%s$normal\n\n" "Trusted mode enabled (press ctrl+c to disable)"
 
 while :
 do
@@ -379,12 +379,12 @@ function disable()
 
 trap disable INT
 
-red=$'\e[1;31m'
-nc=$'\e[0m'
+red=$(tput setaf 1)
+normal=$(tput sgr0)
 
 pfctl -d
 
-printf "\n${red}%s${nc}\n\n" "Firewall disabled (press ctrl+c to enable)"
+printf "\n$red%s$normal\n\n" "Firewall disabled (press ctrl+c to enable)"
 
 while :
 do
diff --git a/how-to-create-encrypted-paper-backup/README.md b/how-to-create-encrypted-paper-backup/README.md
index 39eac4c..6d942c6 100644
--- a/how-to-create-encrypted-paper-backup/README.md
+++ b/how-to-create-encrypted-paper-backup/README.md
@@ -246,7 +246,7 @@ Insert micro SD card into macOS computer, run following and eject card.
 
 ```shell
 volume_path="/Volumes/boot"
-volume_uuid=`diskutil info "$volume_path" | awk '/Volume UUID:/ { print $3 }'`
+volume_uuid=$(diskutil info "$volume_path" | awk '/Volume UUID:/ { print $3 }')
 echo "UUID=$volume_uuid none msdos rw,noauto" | sudo tee -a /etc/fstab
 ```
 
diff --git a/how-to-make-sure-app-is-not-running-in-the-background-on-macos/README.md b/how-to-make-sure-app-is-not-running-in-the-background-on-macos/README.md
index e3364d8..d605f6b 100644
--- a/how-to-make-sure-app-is-not-running-in-the-background-on-macos/README.md
+++ b/how-to-make-sure-app-is-not-running-in-the-background-on-macos/README.md
@@ -83,13 +83,13 @@ cat << "EOF" >> ~/.zshrc
 # Kill apps that match string
 function kill-apps() {
   IFS=$'\n'
-  red=$'\e[1;31m'
-  nc=$'\e[0m'
+  red=$(tput setaf 1)
+  normal=$(tput sgr0)
   if [ -z "$1" ]; then
     printf "%s\n" "Usage: kill-apps string"
     return 1
   fi
-  printf "%s\n" "Finding apps that match \"$1\"..."
+  printf "%s\n" "Finding apps that match \"$1\"…"
   sleep 1
   processes=($(pgrep -afil "$1"))
   if [ ${#processes[@]} -eq 0 ]; then
@@ -97,10 +97,10 @@ function kill-apps() {
     return 0
   else
     printf "%s\n" "${processes[@]}"
-    printf "${red}%s${nc}" "Kill found apps (y or n)? "
+    printf "$red%s$normal" "Kill found apps (y or n)? "
     read -r answer
     if [ "$answer" = "y" ]; then
-      printf "%s\n" "Killing found apps..."
+      printf "%s\n" "Killing found apps…"
       sleep 1
       for process in "${processes[@]}"; do
         echo $process | awk '{print $1}' | xargs sudo kill 2>&1 | grep -v "No such process"
@@ -122,7 +122,7 @@ source ~/.zshrc
 
 ```console
 $ kill-apps adobe
-Finding apps that match "adobe"...
+Finding apps that match "adobe"…
 46639 /Library/Application Support/Adobe/Adobe Desktop Common/IPCBox/AdobeIPCBroker.app/Contents/MacOS/AdobeIPCBroker -launchedbyvulcan /Applications/Adobe Premiere Pro 2020/Adobe Premiere Pro 2020.app/Contents/MacOS/Adobe Premiere Pro 2020
 46645 /Library/Application Support/Adobe/Creative Cloud Libraries/CCLibrary.app/Contents/MacOS/../libs/node /Library/Application Support/Adobe/Creative Cloud Libraries/CCLibrary.app/Contents/MacOS/../js/server.js
 46653 /Applications/Utilities/Adobe Creative Cloud Experience/CCXProcess/CCXProcess.app/Contents/MacOS/../libs/Adobe_CCXProcess.node /Applications/Utilities/Adobe Creative Cloud Experience/CCXProcess/CCXProcess.app/Contents/MacOS/../js/main.js
diff --git a/how-to-spoof-mac-address-and-hostname-automatically-at-boot-on-macos/README.md b/how-to-spoof-mac-address-and-hostname-automatically-at-boot-on-macos/README.md
index 66b47a7..7a646cd 100644
--- a/how-to-spoof-mac-address-and-hostname-automatically-at-boot-on-macos/README.md
+++ b/how-to-spoof-mac-address-and-hostname-automatically-at-boot-on-macos/README.md
@@ -65,19 +65,19 @@ export LC_CTYPE=C
 basedir=$(dirname "$0")
 
 # Spoof computer name
-first_name=`sed "$(jot -r 1 1 2048)q;d" $basedir/first-names.txt | sed -e 's/[^a-zA-Z]//g'`
-model_name=`system_profiler SPHardwareDataType | awk '/Model Name/ {$1=$2=""; print $0}' | sed -e 's/^[ ]*//'`
+first_name=$(sed "$(jot -r 1 1 2048)q;d" $basedir/first-names.txt | sed -e 's/[^a-zA-Z]//g')
+model_name=$(system_profiler SPHardwareDataType | awk '/Model Name/ {$1=$2=""; print $0}' | sed -e 's/^[ ]*//')
 computer_name="$first_name’s $model_name"
-host_name=`echo $computer_name | sed -e 's/’//g' | sed -e 's/ /-/g'`
+host_name=$(echo $computer_name | sed -e 's/’//g' | sed -e 's/ /-/g')
 sudo scutil --set ComputerName "$computer_name"
 sudo scutil --set LocalHostName "$host_name"
 sudo scutil --set HostName "$host_name"
 printf "%s\n" "Spoofed hostname to $host_name"
 
 # Spoof MAC address of en0 interface
-mac_address_prefix=`sed "$(jot -r 1 1 768)q;d" $basedir/mac-address-prefixes.txt | sed -e 's/[^A-F0-9:]//g'`
-mac_address_suffix=`openssl rand -hex 3 | sed 's/\(..\)/\1:/g; s/.$//'`
-mac_address=`echo "$mac_address_prefix:$mac_address_suffix" | awk '{print toupper($0)}'`
+mac_address_prefix=$(sed "$(jot -r 1 1 768)q;d" $basedir/mac-address-prefixes.txt | sed -e 's/[^A-F0-9:]//g')
+mac_address_suffix=$(openssl rand -hex 3 | sed 's/\(..\)/\1:/g; s/.$//')
+mac_address=$(echo "$mac_address_prefix:$mac_address_suffix" | awk '{print toupper($0)}')
 sudo ifconfig en0 ether "$mac_address"
 printf "%s\n" "Spoofed MAC address of en0 interface to $mac_address"
 EOF