I've taken the rear hub off a 2011 1.6 diesel, in order to replace the brake backing plate which had rusted away. If you're going to replace the hub I'd check the condition of the plate to see if it needs replacing as well, because it might take a while to get one. After jacking up the car and removing the wheel, and supporting it on axle stands, you have to take off the brake caliper and the yoke that holds the pads. At this point it may be worth putting the wheel back to feel for how rough the bearing is without the pads chafing against the disc, although it may not show up unless there is weight on it.
Slacken off the handbrake adjuster and take the brake disc off, then you need to remove the brake shoes & springs. The bearing is integral to the hub, I don't know if you can get the bearing separately. The hub is secured by 4 bolts which screw in from the back. They were really tight so I used penetrating oil and heat from a blowtorch to loosen them off. Once they're out, just fit the new hub assembly. If replacing the backplate, you'll have to transfer the slave piston and the rubber boot for the handbrake lever.
Re-assembly is just a reverse of the process, don't forget to reset the handbrake slack. It's also a good opportunity to make sure the handbrake lever in the wheel is moving freely as they are prone to seize up. If necessary, take it apart, clean off rust and scale, and lubricate it. If you look through my posts I've have included ones with step by step photos of stripping down the rear brakes
