First you will need a felted wool sweater sleeve, cut across evenly.

Place your ice scraper handle in the center of the cut end, and cut around it, leaving a seam allowance and an smidge of space on the sides (I left about 1/2 inch all around).

From here, you can just sew up all the cut ends, or round off the corners (which I did), then sew
Kinda looks like a wool wine bottle, eh? Now just flip it right side out...
and push the long skinny part in with the handle of your ice scraper...
and you're done. Wasn't that easy? Now your hand will be nice & toasty while you scrape :).