Most Helpful Guy
A girl I'm friends with had problems with depression and she cut herself. I had no idea until I saw An old photo of her. She uses sweatproof makeup close to her skin tone.
Most Helpful Girl
First, try distracting yourself from cutting. I know it's hard, but once you find a way to distract yourself, you're allowing your mental state to heal along with your scars. That will help you in the long run.
In the meantime, I recommend using MAC studio fix concealer. That stuff is amazing and it's pretty cheap. Also, thin cardigans or long sleeve tops will work fine if it's not too hot out.
Henna or a temporary tattoo will work really well too :)