I'm not a great advocate of handling just for the sake of it, although doubtless many peoples Garters don't seem to mind. Certainly they will seek out warm spots within your clothing etc.

As Stefan says, shedding depends on many factors, and frequent shedding can be an indicator of underlying problems. I don't know if you're familiar with the process, but if not it works like this;
The snakes colours will become subdued and dull. The snake may (or may not) go off feed. The eyes will become cloudy and 'blue-grey'.
After a few days the eyes will clear, then within a couple more days the old skin will be sloughed and you'll have a shiny new Snakems, all resplendent in his new colours!
If you already knew this, please accept my apologies.... I don't want to appear patronising!

I'm not quite sure what your second question was, Sayra!