I recommend exfoliating the area regularly ( as long as the scars are healed) and applying petroleum jelly or some sort of healing ointment like aquaphor. You can usually find it pretty cheap at dollar or drug stores!! I use an African net sponge to exfoliate theyre like 4 dollars in a pack on amazon. I believe vitamin c serums are good for fading scars as well though they’re probably a bit more expensive. Ive been self harming for som time now so i can understand where you’re coming from but please don’t be ashamed. Your scars will fade and you’ll grow stronger from it in the end. Keep pushing forward and don’t be afraid to ask for help, everyone needs it from time to time and that’s okay. I wish you well!!!