I might mention-
High humidity can help a lot, and we have plenty of that here in summer. If your ambient humidity is low, using a humidity dome or putting the cuttings in plastic bags can help a lot. You'll have to put them in shade though so they don't burn. And as long as they're enclosed you won't have to water often.
When I start cuttings inside the house in winter (actually, fall thru spring) I have to use domes because the inside air is so dry.
Karen