Lipstick can leave a stain that is nearly impossible to remove. The trick to remvoing the stain is repetition and patience. Here's how:
Dab the stain with rubbing alcohol. The alcohol helps to break up the pigment and oil in the lipstick. With light stains this may be all you need to get the stain out.
Apply Dawn dish detergent if there is any stain remaining following the application of rubbing alcohol. Use your finger to scrub a dab of the liquid in a circular motion. Start on the back of the stain and then attack the front. Hopefully, at this point, your clothing is stain-free.
If you still have a stain after step one and two, the final round should be a stain stick. There are various brands available, Store brands work just as well as name brands at a much lower cost. Use the stain stick in a circular motion on top of the stain. Finally, run your item of clothing through the wash cycle. Do not dry it until you are certain the stain is gone. Last resort could be a trip to the dry cleaners, but more than likely that will not be necessary.