yah, most of the pressure should be on the rear foot. at some point you should be able to only have to use the rear foot to skid (further allowing you to lock down the one footed skid as well!)
get ready to lock it up on the down stroke of the pedal rotation, as it goes to the rear, extend your leg, and lock it up.
find some gravel/wet pavement/dirt, something to practice. you'll get it from there.
good luck.