This goes for all my main lifts. For accessory lifts I will usually do around 2-3 warm up sets.
Percentages for the most part and the number of warm up sets depends on what percentage of my max I am working with.
I always use at least 4 warm up sets (bare min for rep work) and my last DL 1RM test was 9 sets. I had a Bench 1RM recently that was probably 12 or 13.
As I get closer to my intended weight the increases become slower.
I always begin with 135 and add 1 plate at a time.
If I am working with higher reps I will usually do doubles or triples for the warm up sets...unless I want all the work and I will ramp 10 rep sets until failure to hit 10 reps.
If I were working with 100-150kg I would warm up by 25s (11kg) or 35s.(15kg) plates.
For Squats I will do some quick Yoga Squats, plate weighted ankle stretches and a couple front squat sets but I have mobility issues. For Bench and Dead my warm up is all those warm up sets. No better way to warm up for a lift than by doing that lift with minimal weight preparing your body to do that movement.
edit: should have used your weights!!!! also this is an exact match to the sets I use when working up to 315.