Turn on potato mode: ESC → Display & Graphics → Optimize Settings → Optimize Settings for Performance

Turn off Sound: ESC → Audio → Audio Enabled off

Turn off Chat logging: ESC → Chat → Log Chat to File off

Minimize Local Chat window

Turn off or reduce brackets. This is a bit more complicated, turning off brackets completely can be done with Alt-Shift-Z but that reduces your spacial awareness a lot. Modifying brackets is a subject of a whole guide of it's own but one easy thing to do if you are using the Z-S overview pack is to select a bracket without drones. Open Overview settings → Overview Tabs → Bracket Preset and set * Brackets Combat/Targets/Friendly (-Dro) to your main combat tab. If you ever need to see drone brackets during a fight you can use Alt-Z to toggle between the showing All Brackets and the selected Bracket Preset.

Do NOT zoom in on the action. If possible look away into empty space, if not keep a zoomed out view.

Do no open any unnecessary windows, EVE has a 32bit client which means that if it needs to use more than roughly 4GB ram it will crash and opening for example the fitting window can easily bring it over this.

Turn on Outstanding Calls display: Shift-Ctrl-Alt-M → Outstanding Calls. This will display all orders you have given to your ship (like activating modules and locking things) that not yet been processed by the server. If you see a command do to something listed here you do not need to give that command again as it is already queued up for execution.

Whenever possible use Shortcuts to do things like activating modules, click once and then wait a bit to see if they show up in the Outstanding Calls window.

Make sure you have Corporation and/or Alliance column on your overview (Open Overview Settings → Columms). If a neutral ship or fighter shows up with this colon empty it is bugged and is most likely a friendly ship/fighter, do NOT shoot it unless it's been broadcasted by the FC.