First, simply cut the toe off the sock and roll it up!
2Start rolling from the cut end. About 1/3 of the way into rolling.
When you get to the top of the sock, hot glue the top of the sock cuff to the donut.
Using various colors of felt, cut a square about the same size as the donut. Trim the edges to be circular and irregular. Fold the felt in half and cut out a half circle on the fold. Open the felt and you have a full circle. Use hot glue to affix the felt to your donut.
Now for the fun part! Use fabric paints to create sprinkles! The opaque colors work best, as some colors are too transparent and will dry pretty clear.