This is a popular route for hire boaters from Friesland and can be done in a week, or two weeks if you want to take it at a more relaxed pace. It can also form a mast-up route from the Randmeren to Friesland, as an alternative to the IJsselmeer.
A possible schedule is outlined here, although there are other stopping points along the way, such as Vollenhove and Steenwijk which could be added in if time allowed.
Day 1 Sneek to Echtenerbrug 25km
Day 2 Echtenerbrug to Giethoorn 33km
Day 3 Giethoorn to Meppel 14km
Day 4 Meppel to Blokzijl 29km
Day 5 Blokzijl to Ossenzijl 15km
Day 6 Ossenzijl to Langweer 30km
Day 7 Langweer to Sneek 9km