If you have new tires, and a known good alignment, there is a simple test to figure out what pressure to run.
Find a long straight section of road with no traffic. A long parking lot works too. Air your tires to a good starting point. Use a piece of chalk to make at least three lines across the tread on all four tires. Then drive in a straight line for some distance, without turning (the steering wheel), spinning or skidding the tires at all. Then stop and inspect all four tires. the chalk lines should wear evenly across the entire tread. Adjust the tire pressure and repeat the test until you are satisfied. You may find that you will need a different pressure in the back vs front tires. Naturally, if you load the rear with weight, or tow a trailer, you will have to increase the pressure to compensate for the squat of the tires.
It is often easier to over inflate for the first test and gradually reduce 1 or 2 psi for each test.