Tires

Check the tire pressure regularly - at least once a month. If you don't have the tire pressure gauge, it's really worth to get one. You can find the recommended tire pressure in the owner's manual or on the tire pressure placard (see photo), which might be located somewhere on the car (e.g. on the driver's door opening, inside the gas tank, inside the glove box). The maximum pressure listed on tires is NOT the proper pressure!
Rotate tires at every second oil change - it will insure all tires wear equally.
Feel vibration at cruising speed? - have your tires balanced.
There is a safe limit of the tread wear. If the tire is worn below this limit it's unsafe to drive; your mechanic can check your tires for you.
Uneven tire wear indicates alignment problem.
Improper alignment causes increased tire and suspension components wear and poor handling. In worst case, improper alignment may throw your car into a skid, especially on a wet or slippery road. If a car pulls aside, wanders or feels unstable on the road, have the alignment checked. Properly done alignment will make your car's ride a lot more enjoyable