I don't. I try to avoid the bike when it's icy but last monday (the 6th) I hit a 5-6 kms stretch of solid ice on my way to work and there was nothing to do about it. I fell 4-5 times ( I was going very slow so no harms done) So I had to deflate my tires, they're homemade studded tires so when they're fully inflated the studs don't touch the ground, Once I deflated my tires to about 25-30 psi I had better grip but it still felt very hazardous, I didn't feel like weaving the front Wheel at all.

When I'm not sure about it I ride as if it's solid ice.