I have been doing the lipstick trick, as well. I would mark vertical stripes, maybe an inch apart, across my beard area, then use my fingers to blend it all, until my beard area is a light pink. Then, I would apply concealer, then foundation.
I have been using Ben Nye concealer and cake foundation, but after six laser hair removal sessions, I think I may be able to jump straight to the foundation step now and find a better liquid foundation.
Best,
Cate