This tool has been around for ages...and I really should get one eventually...in the mean time i just use a soft cotton rag or skip the between parts.
Vacuum, brush, wipe, whatever works....but to really clean...take down and soak in the bathtub or shower. I have a couple of large nails painted to match (disappear into) the wall above the shower surround. I can hook one of the blinds up there, then use my hand-held shower wand to rinse them down, spray some cleaner if needed, brush with any large brush. Reverse the tilt. Do the same to other side. Wipe or let dry. Easy to do one or two each week going around the house. Doing them all at once is too much!.