If you don’t have a spotter you can trust, do not attempt a true one-rep max. Your best bet is to estimate your max bench press weight by doing a 10-rep max test.
HOW TO ESTIMATE A 1RM: Find a weight that you can do for 10 reps. The tenth rep is the absolute last rep you can perform with that weight. If you think you can get 11 reps, then you need to rest a good 5 minutes and add another 5-10 pounds to the bar and try again.
Yes, you will still need a spotter to do this properly, but at least the spotter will not have to lift a ton of weight off of your chest. Once you have the weight that limits you to 10 reps on the bench press, multiply that by 1.33. That will give you your estimated 1 rep max.
For example: If you bench pressed 200 pounds for 10 reps:
200 x 1.33 = 266 pounds
Round down to 265 pounds
BENCH PRESS FIVE-DAY SPLIT
MONDAY: Heavy chest, plus shoulders and abs
TUESDAY : Back and traps
WEDNESDAY: Legs and calves
THURSDAY: Light/explosive chest, plus abs
FRIDAY : Triceps, biceps and forearms
*On light chest days, perform reps as fast and explosive as possible.
FLEX BIG BENCH PROGRAM