For the chosen lift you will need to determine your one rep maximum, as the cycle will be based on % of that maximum lift. If you don't know your 1rep max for your lifts then it is probably a good indication that your record keeping is not what it should be or maybe simply that you are a perpetual fluff bunny who doesn't like heavy iron. You can guestimate your one rep maxes from experience if you like, or hold on your cookies, get a decent spot and find out for sure. Your choice!