Depending on the type of paper would determine if I would advise you doing it yourself or not and how.
They are many different types... Vinyl, woven, non-woven, fabric, fabric backed, fleece backed... these are the most common but require different prep, different methods of hanging and different types of paste. Think of it like Ceramic, Porc, mable, slate....
There are also many different types of printing which can affect how you hang it, some you can't get a single drop of paste on, some you can wipe clean, some even require you to wear gloves as moisture from your hands can damage them. OK it's unlikely you'll pick one of them but the point is wallpaper is not just a wallpaper in the same way tiles are not just tiles.
If you were doing a top pro job you would prime the walls with a dedicated wallpaper primer such as Zinsser Gardz, then you'd line the walls. Line walls is not just to give you a smooth surface to paper on to it also has many other benefits, some papers you can get away without a liner, others you'll have problems if you don't