ok I'm trying to learn "for my father" by andy mckee, and I need to tune guitar to :

F C A# F D# G

now I know theres a cabo involved, so I just need help in with this tuning,

i don't know this song or anything (i just watched it on youtube, though), but my immediate response is...

start in standard
tune your A string up to C
tune your B string down to A
tune your high E string down to D
capo on fret 3

that should give you G D# F A# C F (which is what i think you meant), if i'm not mistaken
well, easiest would be to go get a chromatic tuner unless you already have one then just use that.