All you need is the "spray head" with flexible hose [0], plus the adaptor to make a kitchen part fit the bathroom piping (for some reason, kitchen and bathroom have non-interchangeable parts).
You hang it on a hook next to the toilet, and you use it to clean yourself. I cannot live without these, and I intensely regret any overnight trips to a hotel or other place that does not have such an amenity. I regularly recommend and sometimes even buy and install these for friends and family.
The USA is still living in the dark ages when it comes to some parts of self-hygiene.
0: http://ecx.images-amazon.com/images/I/21PJ48yqYmL._SL500_AA3...