is there a trick to grow cuttings from a rose bush?

Easiest time is late summer to autumn with stems that are this year's growth but have started to go woody. Cut pieces about pencil thickness and a hand or so long, take off the lower leaves and the soft tip, and push them a good half their length into gritty compost in a pot. A pot is perfect if you're renting, it comes with you. Rooting powder helps but isn't essential. Then forget about them - outside in a sheltered spot, keep them from drying out, and don't tug to check for roots. Several won't take, so do a handful.