Changing a Faucet isn't rocket science, but it can be tricky if you've never done it before. If you follow this 8 simple steps, you shouldn't have any problems...
1.Before you change the bathtub faucet or even buy the new faucet measure the size of the existing faucets, you will need to know the dimensions of the plates that cover the neck of the faucet that attach it to the wall or tub and conceal the join. When you purchase new ones make sure they are the same size or slightly larger so you don’t have new faucets that expose the pre-existing holes.
2.Turn the main water supply off to the house.
3.The faucet usually unscrews, if this is tight use a plumbers wrench to unscrew.
4.There should be some exposed pipe you can screw your new faucet too. If this is too short or narrow you can buy an adapter pipe from your hardware store or some new faucets kits come with a few bits and pieces for this problem.
5.Tape some plumbers tape around the pipe you are screwing onto. Wrap it around the actually grooves but not too thick. This gives the faucet a nice sealed fit when you screw it on and stops it from having any chance of leaking.
6.If you have a faucet with a plate slide this down the neck of the pipe and now you can screw the faucet to the pipe and make sure it is tight.
7.If you need to tighten it with a plumbers wrench put some cloth around the faucet first. It may make the wrench slip a little but it will stop you scratching your new faucet.
8.If you are changing the taps too you can use the same steps as you would for a faucet but taps normally have a screw in the face of them which are covered by the “Hot" and “Cold" symbols, pop these off and unscrew the taps. Then screw on your new ones too. If you are wondering which way to screw and unscrew always remember “right tighty, lefty loosey".
For more intricate faucet systems see the manufacturers guide on the best way to install.