what's the least painful way to grow a rose bush from a cutting?

Hardwood cuttings in autumn are the least effort. Pencil-thick stem from this year's growth, about 20-25cm long, cut just below a leaf joint at the bottom and above one at the top, strip the leaves. Push it two-thirds deep and leave it alone until next autumn. With heavy clay, don't put it straight in the ground. Either use a pot of compost mixed with plenty of grit, or dig a narrow slit, trickle sharp sand into the bottom and set the cuttings on that. Clay holds water round the base and they rot before they root. Do five or six, not one - a few always fail.