What size or shape of rockwool ?

we like 1 inch cubes, per soak overnight in PH water. Sling the water out of them like a paint brush your cleaning. Put a small hole in the top and put seed in. Cover with rockwool. Some peeps like to put the seed a certain way, It's in the faq somewhere. Put in a warm place and keep moist not soaking wet. A few drop now and then if drying out.

I only do this because of the damage you can do to root when moving. Don't get me wrong I have done the paper towel many times.