Before you start putting your feet on the back pegs i'd get used to your feet on the front pegs, it can be done rather easily.
Get your rpm to your bikes power band, stand up, let off the gas, bounce down an at the same time hit the gas. Try an keep your weight towards the back of the bike, like when you bounce lean back some. It'll take a little getting used to but with some practice you'll get it.
Your hand position on the throttle is gonna be different than sit downs, so it may take a little getting used to.