Stretches & Exercises

Does everyone do finger stretching and limbering exercises before they play? Yesterday, my instructor told me he nearly always does some warmup stuff before playing. Some of it is just stretching (putting the first two fingers of the right hand between two fingers on the left, and making a "V"), some of it is fingerboard exercises.

I have never done this before. But I have very small hands (seriously - my ring finger is a size 6.5) and I find it hard to to form some four-fret chord forms. My instructor, whose hands are marginally larger than mine, played me some five fret shapes that he played with ease.

If you have any specific exercises, mind posting them here?