This is meant to start with your first finger at the 12th fret then repeat the exercise at the 11th fret then 10, etc. Go as far as your stretching will allow you. Play at the position twice where you feel the most stretch while still playing properly. Then continue back one fret at a time till you get to the 12th fret. Rest when you need to. The goal is to play all the way down to the first fret and back up again non-stop with the following points in mind -

1. Think primarily about note quality not speed. 2. When ascending keep each finger in place after it's used until you go to the next string (this works on your stretching) 3. Keep a slight curve to your fingers 4. Play directly behing the frets 5. This is also a good time to develop good right hand technique. whether you are using fingers or a pic, you want to make each movement equal. Alternate equally. If using fingers avoid the tendency to use the same finger to rake when you go to a lower string. That's ok in the real world but for this exercise you want to develop each finger as equally as possible.

Part Chromatic