Azunaki is correct. I would not, however, suggest drawing on the model directly. I have never really had a nicely finished model done this way.
Each model will have an efficient way of texturing it depending on its shape and the level of detail you want. A crate, for example, only needs a "UVW Map" modifier with a box map applied to it if you want all 6 sides the same. However, a more complex model will probably need an "Unwrap UVW map" modifier applied.
For the latter, I would suggest doing a google search for this. Doing this gave me this site:
http://waylon-art.com/uvw_tutorial/uvwtut_01.html
This is a good tutorial for unwrapping a model for texturing with lots of info and pictures to follow. This is the way I do it, and I usually get some nice results. I use 3DS Max 8, but this tutorial and the techniques can probably be applied to any version.