Transfers

Hi -- I am a writer; a character in a novel I'm working on is a t-4 para (man in his mid-forties). I've done a good bit of research but have a particular question I thought someone out there might help me with. He's taking a shower, sitting in a shower chair (lives in house/has a bathroom that was designed with his needs in mind)-- how could he transfer back to his wheelchair on his own? He is insistent about being independent, is in good shape overall, but could he manage this? Thanks in advance for your help, and any general advice and wisdom is welcome. Dan Haas, Copake NY