Try to get a fish bowl thats a bit larger than normal. Give him as much room as possible (although its temporary, dont throw him into something where he would have problems moving around) I would say get an air pump for him, just a small, 5 dollar one would do. Only keep him in there as needed. Plan out the moving of your fishtank so you can get it done as quickly as possible. I wouldnt keep him in there for more than 2-3 days if it can be avoided. Might be necessary to skip his feedings while hes in there though, so the water wont become tainted as quickly.