I've been miniature painting for 10 years.  My technique is never been an issue.  What has been an issue for me the whole time was committing to a paint scheme.  To me picking a paint scheme is almost like a marriage.  You better like what your choosing because without some hassle you're stuck with it.  I have a book of tanks with color schemes and been using the DUST books for source also, but actually pulling the trigger is an issue.  How do you decide what scheme to choose for your army?

 Well, I don't. I paint each unit individually the way I think it would look best.

 Same here, I only do schemes on a per unit basis.

I do online research of WWII uniforms, then make tweaks here or there to fit the "alternate" setting of DT.

I suggest firing up the Google on the internet machine & searching images for things like "German paratrooper uniforms WW2" or "British armor paint schemes WW2" and see what comes up. Usually the images take you to a site where you get lots of different images.

Hopefully, if you don't want to completely ape an historical uniform, it at least gets the ideas flowing.

Hope this helps.