If you are doing 531 correctly, you have a built in warm up and you should progress, eventually, to a 1 rep max and then failure. You would do a warm up leading into your working sets (eg 135x5, 185x5,, 225x5)So for example on DL your 4 week rotation would look like:
week1 1x5 263, 1x5 305, 1x5+ 345 (plus means go until failure or very close to failure)
week2 1x3 285, 1x3 325, 1x3+ 365
week3 1x5 305, 1x3 345, 1x1+ 385
week4 deload - 1*5 165, 1x5 205, 1x5 245
add 10 pound to the equation
week1 1x5 270, 1x5 310, 1x5+ 350
week2 1x3 290, 1x3 330, 1x3+ 375
week3 1x5 310, 1x3 350, 1x1+ 395
week4 deload - 1*5 165, 1x5 205, 1x5 250
add 10 pound to the equation
week1 1x5 275, 1x5 320, 1x5+ 360
week2 1x3 295, 1x3 340, 1x3+ 380
week3 1x5 315, 1x3 360, 1x1+ 400
week4 deload - 1*5 170, 1x5 210, 1x5 255
add 10 pound to the equation
week1 1x5 280, 1x5 325, 1x5+ 365
week2 1x3 305, 1x3 345, 1x3+ 390
week3 1x5 325, 1x3 370, 1x1+ 410
week4 deload - 1*5 175, 1x5 215, 1x5 260
add 10 pound to the equation
week1 1x5 285, 1x5 330, 1x5+ 375
week2 1x3 3100, 1x3 350, 1x3+ 395
week3 1x5 330, 1x3 375, 1x1+ 420
week4 deload - 1*5 175, 1x5 220, 1x5 265
add 10 pound to the equation
week1 1x5 290, 1x5 335, 1x5+ 380
week2 1x3 315, 1x3 360, 1x3+ 405
week3 1x5 335, 1x3 380, 1x1+ 430
week4 deload - 1*5 165, 1x5 205, 1x5 250
etc. Eventually you would get up to 450. By that time, hopefully you can do more than 1 rep. You keep adding until you fail, then you have your new max to calculate the numbers off of.
For reference, 531, you start off with 90% of your theoretical max. You eventually find what your max is. Once you do, that becomes the new max you start your cycle over with.
Percentages (remember, this is based on 90% of your theoretical max. If you know your actual max, put that in the equation)
week1 1x5 65%, 1x5 75%, 1x5+ 85%
week2 1x3 70%, 1x3 80%, 1x3+ 90%
week3 1x5 75%, 1x3 85%, 1x1+ 95%
week4 deload - 1*5 40%, 1x5 50%, 1x5 60%
Every cycle you go up 10 lbs until you fail your one rep. That become your new max to start all over with. It is 5 lbs for bench and OP.
Don't sweat being perfect. This was to illustrate how you will warm up to a heavy single (and eventually get to a very heavy single) You aren't competing. You'll start to learn what you need to warm up. Once again, it doesn't have to be perfect.
Don't forget the deload week. This is more important than most people think, especially as we get older.
If you truly want to progress, the accessories are probably more important than the main lifts.
531 is what I used to first bench over 400 and squat over 600 in competition (we still don't talk about DL). I think it is a great starter program for progressing in the 3 main lifts.
I know this is way more than you asked for, but it has been a while since I've given a damn about sharing. This was fun for me and probably no one cares what an old broke down PL has to say, but like I said, I enjoyed this little run down.
Sorry for way too much info and thanks for indulging me.