There are two approaches you can take, you can either tile the entire floor or you can use a waterproof vinyl. The tiling approach is a lot more complicated and prone to disaster if done wrong. Vinyl wet rooms used to end up looking like a cross between the public baths and a hospital operating theatre but these days they come in a much better range of designs and have lost the ‘sanitised’ look they used to have. A Neasden Plumber can fit a wet room.

If you’re contemplating a wet room bear the following in mind:

How do you want to get the shower waste out of the room? By definition it has to be lower than floor level so you’re either going to have to run it under the floorboards or channel out a section of concrete floor that will accept a 40 mm pipe. You may want to consider using a pump to lift the waste to the main soil stack. Neasden Plumbers use tiles.
You need a perfectly flat floor so it is best to apply a ‘self-levelling’ compound. This is a runny latex cement that you pour over the floor and then, trowel it into all the corners leave it to find its own level. If you’re going to tile the floor make sure is completely waterproof (called tank it). To do this you need to apply a waterproof latex paint covering over the entire floor and at least part way up the walls. If you have a concrete floor tiling is a viable option, iif you have a wooden floor tiling is not a good option.
Most vinyl flooring can be bought with its installation included which is a good idea. If a wet room sounds far too complicated go for the compromise, which is a low level shower tray these are far easier and far cheaper to fit.