Place your car at the level place. Stop the engine. Wait for a while to let the engine oil pour down to the oil pan. Pull the engine oil dipstick (If you don't know where is the engine oil dipstick, check your owner's manual).

Dry it with a clean rag or tissue. Then set it back all the way down into its place.

Now, pull the dipstick again and check the oil level. Normally it should be at "FULL" mark. For example, here you can see that it's lower. It's not a big problem, but it would be better for the engine to top it up. Check the oil condition also: If it's too black, it's time to change it. If it's slightly-brown, it's O.K. If it's dark-brown, but still transparent, it's admissible but better to change it. If it's white (coffee with milk color) it means the engine coolant mixes with the engine oil because of some internal engine problem (for example, blown head gasket). In this case have your car inspected.

How to add the engine oil:
It would be better to add the same type and branch of the engine oil as you already have in the engine. For example, if you have Mobil SAE 5W - 30, SG in your engine, try to find the same. Add a little amount of the oil as it's shown in the image. Wait for a while to let the oil to pour down. Check the oil level again with the dipstick. If it's still low, add some more. But don't overfill it. Don't forget to set the dipstick back and close the oil filler cap when you finished.

Place your car at a level surface. Start the engine. Set transmission lever to the "P" (parking) position, and let the engine idle (on some cars this process may differ, check the owners' manual for details). Pull the transmission dipstick. Check your owners manual to find where such dipstick is placed in your car.

Dry it with a lint free clean rag or tissue. Then set it back carefully all the way down into it's place.

Pull again and check the fluid level. If the engine is cool, it should be at the upper end of the "COLD" mark. If the engine is hot, the level should be at the upper end of the "HOT" mark. If it's lower, you should add some amount of automatic transmission fluid. Check the fluid condition also: If it's too black and has a burnt smell - your transmission is not going to last. Normally it should be clean and transparent, as in the image. Its color may be different, from red to brown. Wipe the dipstick with clean white paper and look at the paper. Normally there should be no black deposits, no metal particles, no dirt left on the paper.

How to add the transmission fluid:
Check the transmission fluid type in the owners manual. For example some Chrysler transmissions need only specific type of fluid and regular fluid like Dexron II can even destroy the transmission. Add a little amount of the fluid as it's shown in the image. Wait for a while - let the fluid to flow down. Start the engine. Check the level again.

Always keep the coolant level full. Low coolant level cause the engine overheating, which is vital for the engine.

How to check the engine coolant fluid level:
The coolant level should be between "LOW" and "FULL" marks in the coolant expansion tank as in the picture. If it's lower, you should top it up. If there is no coolant in the expansion tank at all, you should add the coolant into the radiator also. But remember, Never open the radiator or the expansion tank cap when engine is hot!

When engine temperature is reduced (few minutes after the engine has been turned off) , simply add a coolant into the expansion to "FULL" mark. and into the radiator if necessary.