Oil and filter change.
Warm engine up to normal operating temperature.
Jack up car and support with axle stand. Never, ever go/reach under a car that is only supported by a jack.
Place a container under sump plug area. It will need to hold at least 7 liters but more is better, gives you more chance of getting it out from under the car without spilling oil.
Another point is that the oil will start of spraying towards the back of the car and gradually slow down and end up dripping out – so you need to cover a large area with your container or move it as the flow slows.
Remove sump plug. You will need an 18mm socket, I'd recommend a single hex type as the sump plug is brass and very easily damaged.
When the plug is loose finish off undoing by hand but note that the plug and oil will be hot. Try not to drop the plug into the container of oil. Rags are handy to wipe your hand (and half way up your arm if you aren't careful!) and the plug.
Place another container under the area of the oil filter. This one doesn't need to hold much oil, I use a seed tray.
Keep your eye on the oil coming out of sump to make sure it's not missing or going to miss your large container.
Under the bonnet unscrew the hose clip holding the air trunking, un-clip the the air box cover (2 on the top and one, in the middle, underneath), remove air box and air filter.
If you want better access to the oil filter you can remove the air box completely. Undo the nuts (10mm socket size) holding the trumpets on.
To remove the oil filter you'll need a 'oil filter removal tool'. I use a chain type as there is limited space in the filter area.
(Important point: Close to the oil filter is the starter solenoid, which if you are not careful you could touch with tool/oil filter etc. If in doubt take negative cable off battery.)
Once it's loose undo by hand, it will be hot and messy. Once it's off turn upright and lift out.
Go and have a cup of tea while all the oil drains out.
OK back to work!
Wipe around the sump plug hole and put the plug back in.
Wipe the filter housing with a clean rag. Pour a small amount of oil into the new oil filter (not to much because it will only spill out when you tip the filter on it's side!), with your, clean, finger lightly coat the rubber sealing ring on the filter. Screw on the filter and tighten by hand, do not use any tools, just hand tight is fine.
Fill engine with new oil, I put 5 liters in, wait a couple of minutes, check level and add more accordingly. It usually takes about 6 liters.
Re-fit air box etc.
Disconnect one of the small wires from the coil and if your battery is not in top condition remove spark plugs. Now turn engine over on the starter motor for about 20-30 seconds at a time checking oil level as you go. When you are happy that the level is OK reconnect coil and replace plugs.
The reason for turning the engine over and not starting is to circulate the oil and get some pressure up. Don't worry if you don't see any pressure on the gauge. I don't on mine but I once connected a mechanical gauge and got pressure after about 1 minutes of turning over.
Now start the engine keeping the revs down and watching the pressure gauge. Once pressure is shown on the gauge, get out and check for leaks from oil filter and sump plug.
Run the engine for a 2/3 minutes and then check oil level.
When you are happy that you have no leaks and the level is OK your finished.