First-time brake pad replacement on a 2018 Civic: piston and rotor check

[ThomasH]

I'm planning to replace the brake pads on my 2018 Honda Civic for the first time to save on shop costs, and I've watched several tutorials, but I'm still unsure about a few specifics. I'm concerned about properly compressing the caliper piston without damaging it and whether I need any special tools besides the basic socket set and C-clamp I already have. For DIYers who have done this job, what were the trickiest parts you encountered, and is there a reliable method for checking rotor condition to know if it needs resurfacing or replacement at the same time?