1st thing I notice is that I hate those percentages so I will adjust them and am rightfully annoyed/embarrassed with myself that I shared them at all. (they are an over simplified version of what I personally use.)
The best way to warm up for a lift is to do that exercise with minimal weight. Then slowly add weight until you are lifting with “working weight”.
The percentages are based off of your “last completed” set of that exercise (from now on and in the figure known as “LC”). So lets say for squats last workout you did 5 rep sets @ 135-185-225-255-275-295-315 and failed at 3 reps of 325. 315 is LC. For your next workout you would base your percentages off of 315 which is what is shown in the photo.
If for some reason you fail at or before hitting 295 for 5 you can decide to make your LC 295 or keep it at 315 for the next workout. If you decide you would rather work with less that your heaviest that day then stop adding weight when ever you want (such as if the weights feel heavy or you just feel off etc). You can also add sets after the ramp for volume.
I think most powerlifters use this method and I am pretty there is an article on this site about this and off the top of my head I believe Yates used this method but he described it as 1 working / all out set.
I hope that cleared it up.