When I take on a customer I tell them the work will be done approximately per calendar month. Obviously a calendar month is slightly longer than 4 weeks, so if the 24th happens to fall at the weekend, the work will be done on either the Friday or the Monday, depending on what works best for me (and the weather!). This gives me a fair bit of flexibility for things like bad weather, but it also means that if I want a holiday, I can jiggle things around to make a gap in my round. Last year I was on holiday for 9 days, but didn't miss any work!.