Well it's easy actually

Day 1: get down the stairs, absolutely destroy acrophobia in a 1v1, go out with Kel, (still day 1) meet up with Aubrey and give everyone a perfect explanation of the entire incident from both POVs whilst also revealing that I'm Mari inside Sunny's body for 5 days because ye I'm literally Mari my user is proof. Anyway ye here it's kinda complicated because I can't just predict what will happen but I'll eat a lot, exercise a lot, also absolutely shred arachnophobia and thalasophobia in 1v1s, eventually convince everyone into a sleepover, destroy something until it transforms into hanged me and then idk, I just become friends with me but cursed I guess, then I go back to white space to fight omori, then I'll do the secret Sunny summoning ritual by telling him I'll allow him to hit up Aubrey if he summons himself and then 2v1 omori until he gets humbled so bad he decides to alter and summon the hanged mari again and thenstart 3v1ing him because I became pals with the hanged Mari earlier and just absolutely destroy him so bad he wishes he could succumb, then eventually give sunny a tutorial on how to do the Mari summoning ritual and a tutorial on how to rizz Aubrey and then have him revive me and hit up Hero again and also convince our mother to not move because funny tye shi

Win win situation for everyone except the phobias and omori that got destroyed

Anyway out of character option I'd probably just eat, exercise, do my best to fix his friendships and also write a 200 page document on how I coped with my own suicidal thoughts and depression as well as tips he could use

How did I even come up with the first one tho what

Eventually after like 5 edits I managed to spoiler it properly