Coconut oil will give you a shine/glow but won't lighten too much. Lemon juice is bad, it's too strong and will irritate your skin, making it appear darker. Kojic acid works for me personally, but trying to mix it in yourself can go sour. It's also not oil soluble I believe, you'd need to make your coconut oil into a cream to mix it in or else the oil will just block it from penetrating the skin. It prevents your skin from picking up more tan rather than lightening it though. AHA's (lactic acid, glycolic acid, azalaic acid, etc) are good for actually lightening because they will take off the external layer of your skin, and then kojic acid or arbutin can help to limit pigment production so long as you remember to wear a good sunscreen everyday. Drinking lots of water helps too, especially if you add just a couple drops of lemon juice.