U serious? Overtraining? Do not worry about it at your stage . . in fact if I was again at your stage what I would do is something like this
Use any set rep combination you want 3x10, 4x6, 5x5
After you have completed 1 year of doing that workout and have built a strong base of strenght in your legs and back you can do a small specialization along the lines of this
2x20, 3x15 or 4x10 all work fine. Do that for 2 months and then go back to the maintenance routine. Alternate every 2 to 3 months and you would have completed your first cycle.
Dont forget the diet man!