Wear all black, make sure what you wear is clean, neat and trendy. Wear high heels. Wear enough makeup so that we can see you're wearing makeup. I would go for an elegant, polished look as opposed to a dark stripper eye makeup ( not that I dont love some stripper smokey eyes, I sport that look every other day haha).
Do your research on MAC ! Know a lot about the company!
Best of luck to you!
If you are selected to go on to the makeup interview make sure you recreate the look exactly as it is explained to you...in other words don't add stuff because you think it would look better.