Don't start LST now.
Okay. So, to do a proper scrog you need to take into account what type it is. As indica structure does better in a scrog setup. So. If you want a really full even net.
You want to be topping not only the top of your plant. But look into topping the nodes, this will as you know give you more to work with and train into the net. As if you are only dealing with single nodes, on a topped plant with 5 sets that's 10 you have to work with. (So top them nodes, not all, you have to pick to predetermin where it'll grow best. So you have say 15 nodes you can work with giving you 15 top bud sites and lollipopp most of the stuff that falls below the net by say 20-30cm depending how good you can work it and LST you want to max out on the tops, so more tops makes more sense right. Yes, it'll take away from having big main colas. But it's a scrog not an sog so that's the point.
Yes, you can do it half arsed.. and top it once like normal and train them few nodes but a scrog done right, you only need 1-2 plants and you grow them nodes out into your net. And only way to do that is by topping nodes. And lollipopp anything below or at least until you can see it'll be weak and make sure you have most of it, (lst, lollipoppoing all before you flip.) Then in pre flower. What most ppl do wrong. Is defol to "allow light to bud sites" what bud sites though, until its out of pre flower its still in a state of veg. And bud sites are made by the leafs that are around them. So your net will look full of leafs and you'll see your sites (still in pre flower) covered with leafs, that's fine. When pre flower is over then focus on getting the light onto bud sites..
Look up. Topping nodes to fill a scrog. This will help you. You'll find lots of dif ppls approaches and pick one that suits you buddy.
Good luck