Ako described the process down to a "tee." I would add that it is easier to drain oil from above using a "Topsider" or equivalent. If you do a search on the "T" word you'll see a lot of controversy over draining from above or below. Keep in mind that MB designed these (and most other) engines specifically to have oil drained from the dipstick. It saves you from having to remove the noise encapsulation panel (the true description for what is colloquially called the belly pan), and also keeps you from having to mess with the drain plug. Sometimes they strip and then you have a new annoyance to deal with. With a "Topsider" you do everything from the top of the engine -- after all, that's why those fine engineers put the oil filter housing in such a place that you get to it from above, too!. Also, you drain the old oil right into a reservoir which you transport it to the recycling center-- no fuss, no muss.
Do follow Ako's rec's about using a torque wrench for the top of the oil filter housing (and drain plug, if you do drain from below).