For a part that has a vital part in stopping you from crashing you must ask yourself 'if you have to ask, can I do it'
Your best of getting a Haynes but i'll list what you need to do roughly below
1) jack up car, remove wheel
2) The caliper is in two parts, one is the part that hold the brake pads and the other is the carrier
3) Remove the caliper part (think its a 14mm socket thats needed)
4) Take the pads out of the caliper, give them a clean and then replace the pads. You may need to push the piston back to aid it putting the pad back in. You can do this with a big screw driver or a hammer (handle side on both)
5) Refit caliper to carrier
6) For safety bleed you brakes before driving off.
Job should take about 30 or so minutes.
Mike