There is literally no excuse for not knowing how to do anything anymore. You can YouTube tutorial your way through sewing on a button, shaping your eyebrows, learning French, or Cha Cha-ing in heels, which are all essential fashionista skills.
You can also teach yourself how to do a pretty face of makeup just in time for Holiday parties. In my opinion, you can never go wrong with a little old-school glamour. A red pout with some cleanly lined eyes is the most gorgeous makeup look a girl can go with. It creates a classic face that flatters anyone, and it's simple. Ok, well it may not be that simple if you don't know how to do it. Here's a makeup lesson from the Makeup Geek. She goes a little heavier than I may recommend, but she still covers the basics:
See, you have a computer? You have makeup? You can be glammy too. And you can save yourself the sinus trouble of breathing in huge gulps of perfumed air at the makeup counter if you learn how to DIY this face. Godspeed and remember, less is always more (unless we're talking about fresh baked bread. mmmmm)