Remove your Alfa’s road wheel. (Without the benefit of a hoist, put car in first gear, loosen the wheel nuts slightly, raise and support the rear safely on two axle stands, remove the wheel nuts and wheel)
Remove upper calliper securing bolt.
Remove lower calliper securing bolt.
Remove calliper from brake pad carrier.
Remove brake pad from brake pad carrier.
Using special tool, screw back operating piston.
Clean up brake pad carrier making sure the pads can move freely.
Copper slip rear of brake pads, making sure you don’t contaminate the pad material.
Refit brake pads and then reassembly is the reverse of the above, when you have finished pump out brake calliper piston and then bed the pad in gently for 100 miles.