It's really simple.

1. I buy all my socks the same color, and toss them in the drawer.

2. For an incredibly formal occasion, I might poke around a bit to find a second one that's faded about the same as the first one I pick up.

3. Usually I just try to get a second one with a similar number of holes (to keep things balanced when I limp).

4. I wear long pants, so it doesn't much matter.

I usually try to wear two shoes that are at least similar to each other, but sometimes agonize over whether matching colors or matching shapes is more important for the occasion.

John