Putting on make-up is about hiding your true feelings.
Do you believe you need to disguise your true self from others?
You may highlight your best features to others and refrain from telling them when you're feeling down or sad.
It signifies that you are trying to put the best face on for those around you so they think you're ok when you're really not.
You may value honesty in your life, but you still conceal aspects of yourself from others for fear of their judgement and opinions.
You might think that your true self is not enough, and you need to put on an act in order to appear more interesting and successful in life.
It implies that you are faking it till you make it in an area of your life, if you are putting on too much make up.
If this is the case- ask yourself if this has worked out for you well so far. If not- it might be wise to open up and slowly let the real pieces of yourself out around those you trust.
Another interpretation is that you have low self-esteem and you are using the make up in the dream to cover up your perceived flaws and things you feel insecure about.
On a positive note, it may reflect that you are trying to boost your own self confidence by making some changes in your lifestyle to help boost your self-belief.
It could also mean that it is time to 'make up' with someone you've had a falling out with. Perhaps enough time has passed and now is the perfect opportunity to apologise or settle whatever it is that has caused friction between you and this other person.
It's arguable that putting on make-up in a dream means you have the ability to resolve conflict- so it might be wise to put this to use now.
The Complete A-Z Dictionary of Dreams by Ian Wallace