Keep the Mac awake automatically with Amphetamine
One click in the menu bar stops the Mac sleeping, and Triggers do it on their own while an app runs or a display is connected.
Tips tagged #power
Keep the Mac awake from Terminal
caffeinate stops the Mac from sleeping for as long as you say, or until a command finishes.
Stretch the battery with Low Power Mode
Energy Mode trades a little performance for battery life, separately on battery and on the power adapter.
Look after the battery of a Mac that lives plugged in
Optimised charging and a charge limit stop a permanently connected laptop from sitting at 100% all day.
Decide when the screen turns itself off
Separate timers for battery and mains, so the Mac neither locks while you read nor stays lit all afternoon.