These are made from Lion Brand Jiffy, 100% acrylic. I made 1 slipper from wool ease first, and it was heavy and stiff and scratchy. It hurt my hands to work on it. This Jiffy is NICE to use.
The men's slippers are made using 2 strands of each color, (4 total strands) and you just carry the spare color up the back, and switch colors every 5 stitches. For the little set I used just one strand of each color, and cast on 25 stitches, and knit for 5 1/2 inches length. For the men's (skinny-footed guy) I cast on 35 stitches, and knit for 10 1/2 inches then finished off. I used size 10 1/2 needles. I think for my husband, who has thicker feet, I will cast on 45 stitches, and knit for 11 1/2 inches. As you can tell, it's sort of a figure it out pattern, but they do turn out very soft and cushy.
One last thing, when you switch colors, be sure to cross the yarns in back, or you will have holes in your work.
P.S. Mikey is 3, and he is really trying hard not to tell his dad about the surprise that grandma has made for them.