I like using purples you don't see it that much:
These are from my
Inq Guard blog:
http://www.dakkadakka.com/dakkaforum/posts/list/272476.page
There are some more plasmas in here to:
http://www.dakkadakka.com/dakkaforum/posts/list/283264.page
Simple tip that works for most colours: Start with a dark colour, do 2 - 3 layers of highlights, wash with the desired colour, then highlight again ending with a very thin line of almost white.
If on a vehicle or long enough coils you could paint it in a stripe pulse pattern
Or
Base coat, dry brush with a lighter mix before the rest of the model is started, wash then lightly dry brush again.