I usually pull my hair back with one hand, go like I'm going to pull the band all the way around to do a normal ponytail, but stop halfway, then twist and go back the other way (like normal). That way it leaves the ends of the ponytail out all funky, but it's still back. I imagine a bun would be done in a similar way. Or, instead of being tied back, just use tons of bobby pins to secure it in place and pull out various pieces. It's kinda weird to explain, but I hope that helped a bit.