unless my weed is really moist and sticky, i use about 10-20% more then i want to be in the joint (i have problems with shit falling outta the ends alot too)

where are your thumbs on the paper when you start to roll? at the ends, or in the center? if at the ends, put them in the center, and move them outward as you roll, it helps keep it even so it's not pregnant (skinny ends, fat center)

mostly tho it sounds like you're having problems getting the paper to catch/overlap... just keep in mind, when you're rolling a joint, the more you mess with it, the more is gonna fall out... try to get it even, and rolled up, with as few many 'rolls' as possible...

when you're ready to roll it up and stick it, roll it as normal, then when you get ready to actually overlap the paper, use the tips of your thumbs (starting in the mdidle again) to push the paper down into the 'crease' (in between the bud and the other side of the paper, the side with the sticky crap on it) and continue the rolling motion, but with the 'balls' of your thumbs (the joints in the middle)

edit: sometimes at this point the middle will be tucked, but the ends will kinda still wanna just go straight up, if you continue to roll it and stick it like that, the entire joint is fucked pretty much... (in the center the glue will stick like a normal joint, but at the ends, the ends [glue and non-glue] will be stuck together) instead, hold the joint in the middle and steady with one hand, and use the other to tuck the corners down, then roll it and stick it.