Be the mom. Lay down the law. Tell her she is allowed to wear base, lip gloss, and mascara. That's it. If she's caught wearing more she loses all permission to wear make up.
That doesn't mean she'll listen but it does mean you've set boundaries.
I have seen so many girls choose the wrong base too. That orange stripe around their jaw and chin is soooo unbecoming. It's so obvious it's wrong.
I let my girl wear CG loose powder. I use a mineral powder that is expensive but the CG didn't cost that much. It's also more translucent and not so heavy on her skin. She has that bumpy skin and the base/powder issue is one I'd like to rule on and say no. But it's not effecting the bumpy skin much.
She puts on a small amount of eye shadow. She wears a LOT of makeup in dance and plays so she is very familiar with how the effects can make her look different. I love doing her performance make up. I feel like I've taught her how to emphasize her attributes.
She's only worn eyeliner for one costume, well, two. She did a Shania Twain look for a jazz number where she had a hat at an angle and they were in a dressy looking suit. So the look was similar to her costume for "Man, You Make Me Feel Like A Woman".
That's the darkest and most makeup she's ever worn. So I've been completely comfortable with the amount of make up our girl is trying out on her own.
She doesn't get up hours early to take a shower and do her hair and make up before school yet. She's happy with a minimal look. She's 12 and in 6th grade.
So
Teach her how to use make up in a good way that emphasizes how she wants her face to look. Help her pick the best colors for her skin and eyes.
Make sure you help her find the best cleansing products that will get all the makeup off every night and that will not leave residue.