I'd set up an elaborate scheme to have him broken out of prison by a few of his "supporters," then he'd go underground with my supervision for a few weeks, re-enter Baghdad in a flurry of cheering support for him, and then let him give a long victory speech on the baclony of his palace.
I'd let him rule the country for a few weeks, aided with the assistance of a closed-circuit television system pretending to be the pro-Saddam Iraq news services so that he didn't pick up on the truth.
After those few weeks, I'd reveal the entire thing and have him put back in jail.