In my experience, big girls like to be NASTY!
So, I'd tie her legs wide open and see how much her pussy can take. Use toys (the bigger the better!), vegetables, bottles, and my fist.
Make her take a butt plug while I'm doing that, and might even make her take my dick in her ass with a big toy in her pussy.
And I would be compelled to abuse her titties, too. Pinching, rolling, pulling her nipples, stretching them out so her nipples have to support the entire weight of her tit.
During any or all of this, she would have to lick my asshole and suck my dick until I'm satisfied.
Video and pictures may also be recorded.