I have just discovered an excellent blog (with videos) by make up artist Lisa Eldridge, I have just watched most of the videos and can definitely recommend the 'Removing Make Up' one and the 'Covering Acne' one.
They're available on You Tube too.
I think anyone out there with a self conscious, spot prone, teenage daughter should have a look. Thankfully I grew out of my Acne (without scarring) but I would love to have had someone show me how to hide it!