I used to do it the natural way by eating red candies, fruits (prickly pears do a great job), or lemons (the citric acid would react with my lips to make it more plump and red).
Currently in love with the Sacheu Lip Tint, i use the shade Muah-ve. It takes 5 mins and will last all night. I apply it as a lip liner & inner triangles on my top and bottom lip to give them a little contour and plump, then go over with a clear gloss. ✨✨