You should be doing 1-3 sets per bodypart. Gauge your current recovery ability, and add up the sets weekly. If you do 2 per bodypart, that's 6 sets a week. Compare that to how you used to train (if you did) with training each bodypart once a week.
Start with 1-2, and then maybe 3 for squats if you feel you can.
Strategic Deconditioning is where you take 7-14 days off after every 6-8 week HST cycle, to allow your muscles to become unaccustomed to lifting. They will have adapted to the stimulus by that point, so giving them a break will, in short, "soften them up". This will allow you to break through any possible plateaus in size or strength when you return.
Remember, at the start of every new cycle, add 5-20 lbs to your maxes, depending on the lift and how much you feel you've improved.