How big is the snake? Its easier switching hatchlings compared to adults. A good way to go about it from my experience is get a good feeding response with 3-5 live meals then make the switch to FT. I put my rats in the fridge over night to dethaw then at around 8pm I pull them out and set them under a heat lamp. I've found that helps the scent of rats fill the room and makes my snakes go crazy, then when they're up to temp I offer and by the time I open the tubs the snakes are flying out at me