If you have roughed in mixer taps, the fit off of these is fairly simple. For the shower, all you have to do is mount the cover plate on and attach the handle. Each brand has a different method of doing this although most times the handle is simply attached by tightening with a Allen key from the bottom. Installing the mixer tap on to the vanity is also fairly simple. Screw in the hot and cold water hoses to the mixer. Screw them into the wall, ensuring Teflon tape is used. Silicone underneath the basin mixer as an extra precaution.
Installing taps simply involves placing the tap cover and spindle on the already roughed in plumbing. Ensure you tighten this enough and you’re done.
Depending on the shower head you have purchased, they all require different methods of installation. The most important step regardless of the shower you have is to ensure the water point is screwed on correctly to the shower rose/hose. Make sure Teflon is used on all connections.