First he needs to eat for you a well acclimated feeding BP will switch a little more easy than one that is not.
Feed live for 3 to 5 meals than skip 2 weeks of feeding.
Thaw the rodent at room temp (if fed live rat use f/t rat, if fed live mouse use f/t mouse) and warm up with a hair dryer.
When offering the prey (in the snake's enclosure) hold the prey from behind the neck and move it in the snake cage as if it was alive.