Newer cars have see-through reservoirs with level markings, so you can check weekly without too much effort. Top off with 50/50 solution of permanent anti-freeze and water.
Replace worn, glazed or frayed belts, and tighten them when they have more than 1/2" of slack when depressed between the pulleys. Replace bulging or rotten hoses and tighten clamps.
Do this with the engine warm and running, and the parking brake on. Shift to drive, then to park. Remove dipstick, wipe dry, insert and pull it again, add fluid if needed. Do not overfill!
Remove the dipstick, wipe it insert it and remove it again. If it's low, add oil.
Check Air Filter Every Month or Two
Replace it when it's dirty or as part of tune-up. It's easy to reach, right under the big metal "lid."
Check Brake Fluid Monthly
First wipe dirt from the brake master cylinder reservoir lid. Pry off the retainer clip and remove the lid. If you need fluid add the approved type and check for possible leaks.
Do this monthly in cold weather, weekly in hot weather and daily on long trips. Make sure the cables are attached securely and free of corrosion. Check fluid level. If yours has filler holes add water as needed. Note: do not smoke or light a match near a battery.