Next time you find yourself wide awake in the middle of the night, desperately trying to think of ways to make yourself tired, try taking a few leaves out of David O'Doherty's self-help manual for insomniacs.

Rule number one: counting sheep is just silly; they jump around too much. Try counting something boring, like tortoises or, better still, rocks. If that doesn't work, why not turn on the light and play a game, like pretending your bed's a boat drifting in shark-infested water. Too scary? How about pretending your bed's a castle? Or you could wrap your duvet round your shoulders and pretend to be a superhero . . .

There's an endearing scruffiness to this gentle show, in which O'Doherty and his long-suffering bedroom partner Maeve, leap from one game to the next in a bid to tire themselves out. Both performers have a lovely, gentle rapport with the audience and the daft banter and slapstick is frequently laugh-out-loud funny.

Assembly Rooms, 623 3030, until 25 Aug, 2.20pm, £8–£9 (£7–£8).