This question is often asked and I know there were some checklists before but I think they are no longer available so I made my own (using my words
) that I'll post here:
1) Have Mission idea / Story
2) Edit Missions specs (Name, Type, Squadron, Loading screen, Mission music)
3) Create Background (if skybox used, number of stars = 0)
4) Place Ships / Wings / Waypoints
Edit Ships / Wings (Name, AI class, Persona, Loadout, Player orders, Initial orders, Initial status, Misc settings)
Sexps / Arrival & Departure cues / Directives / Messages
Edit Ships / Wings (Arrival, Departure)
5) Mission objectives / Command briefing & Briefing / Debriefing
6) Team loadout
7) Test, Test, Test
8) Tweaks / Balance / Correct bugs (sexp / typos)
Misc: Reinforcements, Asteroid fields
I probably forget some things but I think it's a good start if a mission have all these things! For briefing / debriefing, I try to always make at least 3 stages for the mission briefing (+ objectives so 4 pages min) and always try to include some sort of bonus or secondary goal if the mission allows it. I also sometimes add an additional wing of tuned fighters that appears only for those playing on difficult or insane (not always as it often breaks balance!)
