haha, i've been using excel since the early 90's... almost 2 decades now lol. i still need help cuz i'm old school and all this new stuff is news to me. i just search around the net for excel tutorials when i'm stuck... some are pretty sick man, just go look! it's hard for me to teach it cuz they gave video's so it was easy to follow.
well first you probably wanna set a foundation on what stats you want to use in ur formula.... and also what equations your formula is gonna want--i already had that before i used excel to accomplish it.