Parts you will need:
Set of Brake Pads
1L Bottle of DOT4 Brake&Clutch Fluid
Possibly a pair of Rear Brake Cylinders
Emery Cloth and Copper Grease
An Assistant (ideally two assistants)

Firstly loosen the bolts on the front road wheels and jack the car up on to axle stands...

Then remove the front roadwheels and slacken the bleed screw (8mm) on the first caliper by half a turn - it is located under a rubber protective cover towards the rear of the caliper.

Using a large G-clamp between the outer-most pad and the back of the caliper piston, tighten it to force the piston into its most inward position and expell the fluid within the piston.

Now re-tighten the bleed screw (not too tight - they snap easily!) See the extra space we've created to accomodate the new, thicker pads...

Now to replace the pads... Remove the R-clip and pull out the pin...

Lift it up and remove the old pads...

Use emery cloth to clean the two grooves on the front and the two at the back that the pads will sit in. Put a small amount of copper grease in these grooves to allow the pads to slide freely...

Insert the new pads and push the pin and R-clip back into place...

Loosen the bleed screw again. Remove the reservoir cap and have your assistant pump the brake pedal until all the fluid is expelled. The reservoir should now be empty - fill it up with new fluid. If you have a second assistant, have them keep an eye on the reservoir and top up as necessary for the next part of the process - if not, you'll have to cover that aswell. Your assistant should keep pumping the brake pedal to pump the new fluid into the brake lines. When the fluid starts flowing smoothly out of the bleed screw and is no longer spitting, have the assistant do one final full stroke of the brake pedal and hold it at the bottom while you retighten the bleed screw. This side is now done. Do exactly the same on the other side.

Now to the rear brakes. Very similar proceedure. The bleed screws on these are 7mm on older cylinders and 8mm on newer ones and is located under protective caps to the top of the drums, just above the brake pipes.

In my case, i sheared one of the bleed screws trying to loosen it and had to replace the cylinder. Cylinders may also need to be replaced if they are leaking or sticking.

To do this, the back end had to be jacked up, handbrake released, the drum removed (2x 11mm bolts) and the red spring between the shoes unclipped. The brake line attachment was sprayed with WD40 and removed (12mm) and the two bolts (10mm) holding the brake cylinder in place were removed.

Then the new cylinder was bolted in place.

The bung was removed before reattaching the brake pipe.

The drum was reassembled and the circuit refilled and bled as previously described.

Finally, go around all four wheels again bleeding them to ensure no more air has entered the system. Ensure the reservoir is at its MAX mark before replacing the cap. Replace the roadwheels and drop the car to the floor and ensure the roadwheel bolts are tight.

The new pads will take some time to bed-in, so on your test run, be sure to give yourself plenty of time and space to brake. You may also notice the fluid level drop slightly during the bedding-in process, so keep an eye on it.

If after bedding in, the brakes still feel a little unresponsive or soft, you may still have air in the system so it may need to be bled again.

Its very unlikely the clutch will be at all affected by this, but if the clutch feels soft and isn't disengaging properly, you may have gotten air in the clutch hydraulic system, as it shares the same reservoir as the brake fluid. To bleed this its a similar process to the brakes, but instead of a bleed screw the clutch slave cylinder has to be bled by releasing the clip near the pipe and pulling the pipe out slightly.