I don't know, this might seem odd to people...but I wipe sideways.

Ew................

The most sanitary method is definitely upward.

All sideways would do is smear your crap all over one of your cheeks.

i wipe away from the junk, but more importantly i wipe FAR more than neccasary. it consumes toilet paper at an alarming rate but it does insure that there are no little brown road lines in my underoos later on. also, i fold, i dont wad, i cant stand the idea of perfectly straight edges being anything other than perfectly lined up and even, and i always use a number of squares that is divisible by four. this doesn't help the wiping at all, but thats the way i must have it. i also must make an effort not to COUNT my wipes, or ill soon be wiping extra just to round it out to a number i can tolerate. but then more wiping is better than less wiping i suppose. as for overhand or underhand tearing, it doesn't really apply to me. i dont like having my toilet paper restrained by such a devise, so i typically just leave the roll resting on the counter untill needed.