i started out with 18 pullets that were approx. 2-3 months old. i had just built a spiffy new hen house, and put pine and wheat straw on the ground, in the fenced yard and the enclosed area. the first few nights, mine also grouped up on the ground, in a bundle. i waited until it was dark, and picked them up 2-3 at a time, and put them on the roost. after 3-4 days, they caught on, and hopped up there. i put an upside down milk crate in front of the roost, as the first slat was about 24''-30'' off the ground. they would hop on the milk crate and jump right on the roost, climbing the slats to the top. i put 5 slats at the top, approx. 2'' apart, so they could squat at night if desired, and the poop would fall clear.i ripped treated 2x4's for slats, i remember clear as a bell, grandpaw used elm or oak saplings about 1''-2'' around.