Do not use a single N-Gon (polygon with more than 4 faces) for texturing, it will not make your life any easier, trust me.
– J SargentMar 11 '15 at 16:45
@SimonDülpers There are various ways of remove extra geometry, e.g. http://blender.stackexchange.com/questions/14308/how-do-i-remove-subdivision-loops and http://blender.stackexchange.com/questions/21082/is-there-an-unsubdivide-function-in-blender
– Ray MairlotMar 11 '15 at 17:54