You can make a homemade version by combining a little water, ammonia, and anti-freeze together or most stores carry it cheap enough. Lights Check your lights often. If any of these lights are not in working order, you can be legaly fined. Check headlights, both dims and brights and don't forget the tail lights. Most of the time if any of these lights are not working, all you will need is a fuse.
Battery Make sure all the connections are good and there is no corosion.
Most batteries today have an indicator level on them that will show when the battery is getting low. Batteries are easily replaced at home. Engine Listen to your car. Strange sounds should always be check out. It is much better to catch a problem early on as it may end up costing you much more if you let it fester.