My favorite because I suffer from mild adult acne, is asprin/dispin masks.
You take some asprin, the type you mix with water, you add a few drops to make a paste, if you apply it directly to a pimple it will shrink it and take away the soreness.
You can also use it as a facemask, but it will leave your skin red and sensitive so be extra careful and test it out on a small area first.
It is the salicylic acid ingredient that helps
For dark shadows, I use a concealer but in a light colour, then I add a shimmery white eye shadow over it, the sparkles reflect light so that helps a wee bit. Also using a shimery eyesdow in the inner corners of you eyes looks pretty good. Also pat on the concealer don't rub it in or it settles in the crows feet.
Makeup brushes are expensive! I do have a foundation brush, but I buy all the rest of my brushes in the art shop for a few euros, the ONLY difference is the handles are a bit longer.Also it's hard to find eye shadow brushes that are shaped with an angle, I like to use them to apply eye liner using eye shadow so it's a good thing the art shop sells them
If I don't have power I just use baby power, it's also great if your hair is greasy and you don't have time to wash it, you can use it as a dry shampoo.
Baby oil is good and safe for removing eye shadow and mascara with.
I use dove soap a lot. It's cheap and lasts for ages and it PH balanced which is good.
um thats all I can think of at the moment