Avoid unnecessary hidden files like .DS_Store on Mac

Each file occupies 4k, which can become a lot of waste in disk space and speed.

Based on this webpage, use the following command to disable MacOS from creating those hidden files on network and USB drives:

defaults write com.apple.desktopservices DSDontWriteNetworkStores true

defaults write com.apple.desktopservices DSDontWriteUSBStores -bool true

Another elegant way is to use TinkerTool or CleanMyMac.

Switch off internal display of MacBook when connected to external monitor

When connected to external monitor, MacBook still has its internal display turned on. This dual display mode consumes GPU power and drags down performance on graphics and games. BetterDisplay is a powerful tool to customize tones of settings, including turning on/off each display/monitor connected.