Tools needed:
1x Flathead or Philips screwdriver
1x 10mm spanner
1x 9mm spanner
lots of rags
1x bleeding kit (piece of tubing with a 1 way valve at the end)
To start of, park the car with the nsf wheel on the kerb. This lifts the left side of the car and aid bleeding (see below). Alternatively, jack left side of the car up.
Open the bonnet and identify the cylinder. It'll be under the air box on top of the gearbox.

Remove the airbox. This is done by unscrewing the jubilee clip from the hose and unclipping it from the bottom. Disconnect the air sensor and take care not to damage it. Put the air box in the boot to avoid accidents. I also unbolted the air box holder bracket thing as you get a much better access to the cylinder.
Here you can get a better view of it.

Remove the slave cylinder cover by unclipping it, remove a spring clip from the hydraulic pipe, taking to avoid leaks. As you'll see in these pictures, I failed to do that resulting in hydralic fluid everywhere! It's nasty stuff, so mop up any spillages promptly. Put rags everywhere you can.
To undo the cylinder itself, push it towards the gearbox and turn it 90 degrees anti-clockwise. It's a bit awkward but it will come out eventually. Here it is removed.


And my new one:

Refitting is reversal of removal - so, push it into the gearbox, with the pipe connector facing down and twist it 90 degrees clockwise to lock it in. Note, that the push rod on the new cylinder is fixed with some retainer - don't break it off. It will snap automatically during bleeding. If you do break it, I'd imagine it will be more difficult to fit it. Then refit the hydraulic pipe and put the spring clip back in.
BLEEDING! The worst and the most fiddly part of the job. First, fit the bleeding tube on the bleeding nipple at the end of the slave cylinder and put the other end into a coke bottle. Undo the bleeding nut with a 9mm spanner.

Open the brake and clutch fluid expansion bottle and fill it to the brim with the DOT4 hydraulic fluid. The pipe from the bottle that takes the fluid to the master cylinder is, stupidly, on the side of the bottle, hence the reason to lift the left side of the car up.

With the bleed nipple open and bottle full, pump the clutch pedal by hand several times. Keep watching the fluid in the bottle and keep brimming it if it goes below the pipe hole. After a few pumps the pedal should become stiffer and you should see the fluid going into the coke bottle from the cylinder. Keep pumping until there are no air bubbles in the clear tubing. Once this is done, close the bleep nipple and pump the pedal by foot around a 100 times. By this time, the retainer thing on the cylinder push rod should have broken and should be making contact with the gearbox push plate.
Refit the air box and that's it.
Waiting for the post man to bring me some feeler blades, so I can start doing my rocker cover gasket.