Skin care tips! *May be graphic (not really)*

Hi guys so i'm 16 and I used to suffer with really bad acne starting around middle school ( puberty sucks -__- ). Well now i'm a junior in high school and while my acne has calmed down a great great deal, I still suffer with ugly dark marks. This causes me to feel very self conscious and I rarely leave the house with no makeup. I was just wondering if anyone had any tips or tricks to lighten these scars. I was hoping before school so in about 3-4 weeks! The discoloration is terrible :( it makes me feel so ugly..