Hon, you might try what gainesvillegreen suggested. It's what I do. I let the seedlings grow until they have about 1 1/2 - 2 inches of growth above the 4 set of true leaves. Then I top them. The seedlings start putting out side branches and you should get 2 main colas with any luck.

Meanwhile, the snipped cuttings get their largest leaves removed as well as at least the middle leaftlet of the remaining leaves. I'm a "granny-style grower" and all I do is grab a ceramic cup, fill it with our lovely well water (no chlorine or anything), put some foil over the cup and poke a few holes for the clones. They get labeled and put into the closet with the "big girls" under 12/12. Most will set roots even as they sex out. As soon as they sex, they are put back under 24/7 or killed. But then the females have to reveg, which takes time.

And revegging can be a problem with some plants! I have one "sexing clone" plant that refuses to completely reveg- no lowrider in it as far as I know. She is happily setting buds under 24/7! If I didn't LST her, she'd be about 15 inches tall and she has several nice 2 inch buds. She gets to go under 12/12 this weekend. From her looks, she will be one solid mass of bud when she finishes! I took a clone of her when I topped her, and she too, is trying to set bud under 24/7.

Revegging "confuses" the plant and, IMHO, slows growth. Let your seedlings veg and get big, while you sex them with cloning. - Granny:hippy: