I got a box of strips as a gift. I don't really care about aesthetics, so for me they were more hassle than they were worth. I was in a compression vest for 2 weeks post-op. I think for most people it is 4 weeks. Every surgeon is a little different in when they'll allow you to use scar treatment, so best to ask yours. You have to be healed before you can use them is the main thing.
I used them a month or two post-op, for a month. I cut them in half, then lined them up over the incisions. I would take them off when I showered, soak them in warm water, and put them back on. I don't think I waited for them to dry. I would get about 3-4 wears out of them before needing to apply new ones.