First of all you need
Image editing program
unity3d file of what you are editing
Honeyselect colourable tag: 4E2D (just remember this)
Finished retexturing tutorial(knowledge)
All you really need to do is open up the unity3d file
Find the texture make it white/grayscale instead of whatever colour it is.
Open up cf_n_O_root and the other folders until you reach something like this, add the tag 4E2D to the ones you need(open them, there are still stuff in there), press apply and save everything. And now you should have a working colourable item