Safely lift the front of the car so that you can reach the oil drain under the engine. I highly recommend ramps because they are the cheapest, simplest, and least hassle.

The e90 may be low enough in front to consider buying lower-profile Race Ramps.

If you're using a jack instead, never forget to use jack stands. It's absolutely crazy not to.

Remove the oil filter cap. It's a black round cap under the hood, located at the front right side of the motor right on top.

You will need a filter wrench or strap wrench to remove the cap, it just unscrews counter-clockwise.

The oil filter is right under the filter cap, just pull it out and place it in a plastic waste bag.

Locate the the oil drain bolt under the car. The entire bottom of the engine bay is covered with a large plastic skid plate, which hides the bolt. There is a trap door in the skid plate that covers the drain bolt.

Open up the oil drain flap, and remove the 17mm drain bolt. Make sure you have an oil pan to catch the 7 quarts of oil that will come pouring out.

While you're waiting for the oil to drain, go back up top and install the new oil filter.

Make sure to replace any rubber O-rings that come with your new filter.

Then simply slide the filter in place.

Re-install the oil filter cap and tighten it with your wrench to 25Nm.

Get back under the car now that all the oil has drained, and screw in the oil drain bolt.

I usually use a clean paper towel to make sure no debris or sand gets into the bolt's treads. Tighten to 25Nm. You should replace the crush washer to prevent any leaks.

Close the skid plate door, and clean up any mess you made.

Remove the oil fill cap, its a square topped cap located on the top of the engine.

Pour in all 7quarts of the delicious synthetic oil. You may wish to use a funnel to keep things from getting messy.

Tighten the fill cap back down, and rejoice.