Open System Settings
Click Lock Screen
Set “Turn display off on battery when inactive” to Never
Set “Turn display off on power adapter when inactive” to Never
Open System Settings
Click Battery
Turn off “Put hard disks to sleep when possible” if available
Turn off “Slightly dim the display on battery” if needed
Open System Settings
Click Displays
Increase the display sleep timeout if available
Open Terminal
Run `caffeinate`
Run `caffeinate -d`
Run `caffeinate -i`
Run `caffeinate -s`
Keep the Mac plugged into power
Keep the lid open on a MacBook
Use an app that prevents sleep
Check Energy Saver settings on older macOS versions
Disable scheduled sleep in System Settings
Close apps that may trigger sleep settings
Restart the Mac after changing settings