2 or 3 is plenty you want to learn to get down and as far forward as possible.
Mine is 2 pieces of 1/8 ply 1/12" wide laid on floor along sides with 1 strip in the center and 3 steps aproximatly 11/2 X 5/8 or 3/4 use some hard wood oak birch or ash as your spikes will chew it up. Round front edge where your heels might hit . If want it removable lay some viscuine under everything and assemble with epoxy. you can then install with a couple of small screws
or double sided tape. otherwise you could just glue the steps across floor permanetly.
here is alink to kent composites check his design
http://www.csi-composites.com/hulls.htmGet out on the ice and look around
rasty
Dn1313