If you dream your rival is wearing lipstick and you aren’t, you may fear she is going to win over you in a romantic situation.
If you dream that you put on lipstick, you are growing confident in your female powers. Putting on lipstick can also mean masking communication, so dreaming of someone else putting on lipstick suggests they may be keeping some information or truth from you.
To dream of buying lipstick at a store is very lucky - the more you buy, the luckier you will be in real life.... My Dream Interpretation
Anything that is associated with the mouth is going to connect to aspects of communication. Lipstick highlights the mouth in an overt way that also has some sexual overtones. For a woman, lipstick may be indicating a need to pay more attention to the strength and command of your voice. For a man, it may be calling for a need to soften and adopt a more feminine approach to what you feel you need to say.
If someone is wearing lipstick in your dream in a way that seems important, that character aspect may have something to communicate to you.... Complete Dictionary of Dreams