Materials:
Milkshape 3D
Quark
Photo Editing Program
QME 3
ok lets get started!
we're just going to be making a box but it will show you how to get your models in mdl format to use ingame!
open milkshape then make a box.
here's mine:

as some of you might be able to tell i just used a texture off of google. which what ever texture u use MUST meet the quake 1 pallet. which the one i used does nicely

, but ill address all of that in another tutorial...
ok next save it as a
MD3 file!

once done with that load up quark and open your new md3 file into it.
then save it as a .mdl through quark!
open up qme 3 then open your new .mdl the skin/texture prolly looks messed up or weird just reload your premade texture again and then save!
your all done!