I am interested to know who periodically does their own checks on their cars and what they do, how they do it and how often?

I will start off but I am starting this so I can possibly learn some others to add to the list.

Checking: Tyre pressure
How often: Weekly sometimes bi weekly
How: Digital pressure gauge

Checking: Suspension problems
How often: Weekly
How: Jumping up and down while standing on the foot wells and visual inspection (please tell me a better way LOL)

For me, same as you for the first one:

Checking: Tyre pressure
How often: Weekly on a Thursday night. Spare tire on a monthly basis.
How: Kincrome digital pressure gauge

Checking: Tread wear
How often: Bi-Weekly
How: Visual and by hand

Checking: Fluid levels (engine oil, coolant, power steering, washer bottle top up)
How often: Monthly
How: No explanation needed.

Checking: Brake pads
How often: Monthly (then every second week as they wear)
How: Visual inspection after taking wheel off.

Checking: Air conditioner
How often: Weekly
How: Just making sure I run it for 15 minutes once a week. I rarely use it... even in summer.

Checking: Cabin air filter
How often: Monthly
How: Visual inspection

Checking: Drivetrain/suspension related nuts and bolts
How often: Every second month
How: Jack the car up and make sure things are tight.

i kick the tyres, to check tyre pressure. done..... drive away

K mart - 15 $ digital tyre pressure gauge and fair accurate

swinging my foot at a tyre is free....

tyre wear and pressures weekly with digital guage

check all fluids fortnightly

suspension related attachments/bolts and brake pads every oil change (2 months)

run air con for 1 day each week (around about 15km)

pretty basic stuff, but also get it serviced religiously so nothing much really goes wrong

i like your attitude keep it up dood ! and i do the old look at it and compare it to the rest and the old kick the tyre, if it falls off then ill be worried lol