Section 17-15 gives a pretty clear guide to replacing the pads, and should be simple.
Remove rubber plug at rear of caliper, (Pry pads apart gently with screwdiver to give clearance for removal)
Remove Stop bolt found in the hole ( uses allen key).
Pads should drop out. If needed, use old pads to help compress brake piston inside caliper
Fit front(outer ) Pad, and partially fit stop bolt ( ensure the leading edge of pad is securely located in slot).
Fit inner pad, and do up stop bolt, refit rubber plug. press brake to pump up caliper.
Job done.