When are my seeds ready to plant

I am germinating with the paper towel method. I am wondering how far I should let the root out before planting

You want the root about less than 1 cm long. Also don't touch it with your fingers. Gently do it with tweasers or something.

I just wait til its cracks the shell open and i take teasers and take off the shell the entire way [if it doesnt just fall off first], but yea, be careful not to touch the little root

Thanks