We use Macs, this is what we use to keep them performing well:
Remove unused files CleanMyMac3 (finds large files you’ve not used recently, deletes unused language files, old caches of data you don’t need etc)
Manage Your Startup Items Go to your System Preferences > Users & Groups and then click on your username. Now click on “Login Items,” select a program you don’t immediately need when your Mac starts up, and click the “-” button below.
Update Your OS An obvious fix but one that can work wonders, keep all software updated.
Upgrade your RAM / SSD (doesn’t apply to all Macs) Use the Crucial Ram checker to find if you can upgrade Upgrading your SSD will depend on the age of your Mac. Anything newer than 3 years old won’t be able to be upgraded but something older should be able to!
Use Atext or Text Expanders to speed up commonly written things For instance if we want to write ‘Thank You’ we simply write ‘TY’ and it automatically writes it for us