Turn down the graphics: ESC → Display & Graphics → Optimize Settings → Optimize Settings for Performance

Turn off sound: ESC → Audio → Audio Enabled off

Turn off/reduce brackets. Turning off brackets completely can be done with Alt-Shift-Z, but doing so reduces your spatial awareness. Modifying brackets is difficult, but if you are using the Z-S Overview, 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 Show All Brackets and the selected bracket preset.

Make sure your Mumble client is configured correctly. Specifically, ensure that your whisper/shout keys are properly configured and you know how to use each of them. Click here for a GIF that describes this process.

Close any unnecessary windows to free up system memory.

Turn on the Outstanding Calls display. CTRL-ALT-SHIFT-M → Outstanding Calls. This will display all orders you have given to your ship (activating modules, locking targets, issuing commands to fighters, etc.) that have 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 by the server. Wait until it has cleared from the window before issuing subsequent commands.

Double check your consumables and other resources. Cap boosters, fuel, strontium clathrates, fighters, ammunition, drugs, mobile depots, ship maintenance bay contents, anchorable bubbles, GTFO packages, mobile cynosural inhibitors, etc. Once you jump, you'll have to make do with what you've brought with you. Don't be "that guy". That guy slows the fleet down and distracts the FC and your fleetmates from more important tasks. Be prepared and bring more than you'll need.

Get plenty of rest, eat a healthy meal, and drink some water. A fatigued and grouchy capital pilot is an ineffective capital pilot.

Take a deep breath. You are jumping into heavy tidi and will likely be waiting minutes between individual commands. Expect a slow pace.

Undock only when the FC says to undock. Jump only when the FC says to jump. Only jump to the cyno that the FC verbally identifies by name.

Take another deep breath.

Boost your capacitor to 75% as soon as you're able.

Listen to the FC's instructions. If anything is unclear, wait for a quiet moment in comms (there will be plenty during a long tidi brawl) and ask for clarification. Use specific questions to get specific answers. "What are we doing?" is not a specific question. "What is our passive align?" and "Who is our current primary target?" are specific questions.

Use keyboard shortcuts to do things like activating modules whenever possible. Click once and then wait a to see if they show up in the Outstanding Calls window.

LISTEN TO THE FC'S INSTRUCTIONS. Capital FCs have a tremendous amount of information being fed to them at all times and are extremely busy, especially in heavy tidi. Be patient, don't argue, and enjoy some pleasant banter with your fleetmates as time allows.

Check your capacitor periodically to ensure that it remains at jump cap (~75%). As the fight draws to a close, the window for extraction could become unexpectedly narrow.

Verify your push-to-talk keys in Mumble and use them appropriately. The very last thing a capital FC needs in the middle of a maximum-tidi supercapital brawl is someone using their shout key to talk about the funny thing their cat just did.

Stay hydrated and have fun. Maximum-tidi capital fights are the engagements that define the political landscape of New Eden. Take pride in your part in it, and enjoy the many times you will have the opportunity to proudly proclaim "I was there!".

When extracting, jump only when the FC says to jump, and only jump to the cyno that the FC verbally identifies by name.

Dock up immediately: you are unable to tether for quite some time after jumping to a cyno, and a properly placed and timed dread bomb could spell the end to your shiny supercarrier.

Replace any resources you may have consumed or lost during the fight. Fighters, fuel, drugs, and anything else. Ensure that everything is topped off and squared away. It will make your pre-flight checks for the next fight go smoothly.

Thank the FC.

Regale your alliance mates with tales of your sweeping victory.

Post about it on Reddit.