Ok so lets make it clear . U would like to make a model of yourself for WC , right ? First get a references of yourself . Make a model but dont make it too polygonal . Just model the base shape and make it a bit exaggerated so it would look better in wc environment . Then you need to texture your model and this is the most important part since wc models are very low polygonal and texture contains most of the model"s details . U can just put your photo textures on top of your model and it will look like total piece of crap but maybe someone will tell you that it is very good :) But if you want really good model then you have to paint your textures . Do not think like you have to paint from scratch ! Nowadays nothing is made from scratch :) For example how ppl make those next gen textures with so many details ?! They just model all of the details and then use render to texture to capture all shadows of these details and then just paint some colour information on top of the shadow layer :) But for your case it is impossible to do because your mesh is very low polygonal . In this case your photo references will play most important part in texture painting . You will ask how ? I ll tell you :) First take a look at this picture :
How I made it ? I just took few photos and painted over them . You could use exactly same technic for painting your textures . So take a photo of your face and just start painting colour over the photo . This is easy to make and it will look much better than just a photo .
Anyway I hope this helps a little :)