This is a pretty general workout, not really specific to skiing itself, but important for building general strength in the early season. It starts with a warm-up, something around 15-20 miutes of easy running or biking, whatever's convenient. Then, into building beach muscles!
We generally do three sets of each exercise we do, with 8-15 reps per set at a weight which is close to maximal for that number of reps. Another technique for building strength, and hopefully avoiding plateaus, is to do a light warm-up set, then one set very close to max for as many reps as possible - this should be around 5 - then two sets of a weight a bit lighter, to do about 10 reps for each of those sets. We've been using this technique for leg presses and bench presses.
Among other exercises we tend to do are lat pull-downs, calf raises, dips, hamstring curls, leg extensions, shoulder presses, pectoral flys, and chin-ups.
Finally, we do a warm-down, similar to the warm-up.
The idea behind this workout is to improve general strength, so that when more specific ski strength becomes more of the program later in the year, there is already a good base, and all the weird little muscles involved are hopefully strengthened.
Many leg exercises can be done with one leg at a time. If possible, this is a good idea! Think about it - how often in skiing are you using both legs at the same time? Using one leg at a time recruits more muscles, and helps avoid assymmetry.
It is very important to concentrate on good technique, so as not to injure yourself! For the same reason, don't start at a weight which is too heavy - work up to it - and exercise with a friend who can spot you on maximal weights.
Remember not to ignore non-ski-specific muscles. Opposing muscle groups are very important - say you were to ignore your bicep and work only your tricep, the likelihood of injury would increase!
Have fun! And remember - when you look good, you feel good!