there are few routines out there but i use it to start my leg workout - the rest is icing on the cake
its one set. and don't be afraid to challenge yourself, but you'll only use about 50% your 1RM - but thats just a guess. for your first time if you're doing it with your bodyweight on the bar thetas pretty good - IMO
but yeah - one set, 20 reps. it usually goes something like this...
1-5 - okay - no biggie, getting warmed up
6-10 - alright feels good, starting to get a little burn
11-14 - getting a little difficult
15-17 - alright its in my head now, i don't think i can do any more
18... so tired...
19... almost....
20. wow.
when you get done you should be exhausted, legs burning, breathing hard, etc.
its very stressful if done right.
you can't add much weight each week but try to add between between 5 and ten pounds.
you can also use it as an occasional training method to shock your body - just keep your eye on your weight