It's very easy
1) remove brake hose bracket
2) remove the 2 caliper bolts (behind the caliper)
3) remove the caliper (lifts out)
4) remove the pad shims, pads and retainers
5) give everything a clean, grease up the retainers and shims
6) you will probably need to rotate the piston clockwise to make room for the new pads (grease the boot so stop it twisting with the piston). Also align the groove on the piston with the notch on the back of the pad.
7) put everything back together in reverse order
Job done! 8)