When there's 1 to 2 inches of snow, and no ice underneath (which is a rare combination here), I like to ride my mountain bike. A very small lean with sideways pressure on the tires starts them slowly sliding out.

So I ride very balanced over the bike. It's interesting how I start to really notice the balancing effort. On a dry road, it's easy to just steer a little, instead of trying to stay balanced. Snow riding must be a little like riding on rollers.

Even so, the tire track does show the different tracks of the front and rear wheels, even riding on a straight line.

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Like the other posters above, I also like to ride on the fog line, and it works best when not trying too hard, and when looking down the road.

Now I need to practice a steady effort for pulling a group. I tend to push a little too hard on slight rises in the road. It's really nice to be behind a competent rider holding a steady pace.

For group rides, at least try to see the riders in front of the rider directly in front of you. I don't like being behind riders that roll up too close to the rider in front, then slow down, opening a gap, and then do it all over again. Grrr.