Mostly you’ll learn all about watching paint dry.My advice is to realize you’re not ready to take them yet and it’s gonna take however long it takes. Read a book. Do a puzzle. Lol!!! This is for me the very hardest part, and it’s only hard cuz I am not always as patient as the goddamn plants! As you said, you still have 60% that are useless right now, ie, they haven’t filled with white. Remember I was telling you how the damn things never cooperate on trichomes? Lol! Whether or not you can picture it well, keep watching the trichomes. This is your first legitimate opportunity to learn this for yourself and you are in the enviable position to learn something that took me and many others a really long time. Your plants look fabulous and the buds are at the perfect point for you to witness this yourself. It will serve you extremely well my friend to see how the trichomes age and change over the last couple weeks. See the rate with which they change. See how it doesn’t actually go clear - white - amber all over the plant all the time nice and clean like that. That would be Nirvana! Unfortunately it’s not reality. Instead, what we see is generally they go from clear to white to amber. And sure, each single trichome will do that pretty much if you just looked at a single one. But only extremely rarely (I’ve seen it maybe twice ever) does the plant as a whole do that. I can see this one won’t either, lol. So soon you’ll have mostly white, a few half filled, a few early (light colored) ambers and maybe a dark amber or three. Different parts of the plant will show differently depending on many factors. The uppers will generally look done before the lowers or small hidden buds at the bottom. For example: you might check the top of a cola and say oh they’re ready I gotta take this plant. But if you look at all the buds only rarely will they all be “ready” (by trichomes) at the same time. You just gotta take what’s mostly happening with them to make your determination. Know what I mean? Check buds trichomes all over the plant. Sometimes it’s advantageous to take the upper buds if they’re ready, but leave the lower ones to finish a little more. It’s a staggered harvest or whatever you wish to call it. Partial harvest. I do it often and should have with the big Gorilla Cookies. Would have cut down on the flarf. Lots of folks do that, someone will likely chime in on that one. Anyway just watch what happens as closely as you can. It’ll be learning you’ll appreciate for a long time I promise.