DIY Vinyl Top install question

I've watched videos and seen them pull it off many times after laying it down, but not after forcing it down tight ? Some stretch tight and some don't?
I'll be doing mine, but i've never done one yet?
You can move it for a short time, but with 2 people! you'll never make it by yourself... at least I sure wouldn't be able to.
Only stretch it enough to get the wrinkles out, stretch it too much and you run the risk of it shrinking back up over the next few years- and pulling out from under the trim.