Then I take a puffy paint designed for fabric and draw little designs on the bottom of the socks. The slick version of the paint works the best. I find the matte colors dont work so well as a non slip tread. Put a thick layer of paint on and let it dry really well, atleast 6-7 hours. I like to leave them overnight to dry.
(It does put a damper on those 'indoor ice skating' parties that my kids like to have..... pretending that they are ice skating while shuffling their slippery socks along the kitchen floor. Save one pair of slippery socks for those special times!)