Firstly never pop or squeeze a pimple. Let it heal on its own.
Try these remedies for the spots you already got –

1. Make a paste of sandalwood and rose water. Apply this on the affected areas. Wash with warm water after drying. Sandalwood is very effective in removing the acne spots.
2. Apply inside of papaya skin on your face and wash with water after an hour.
3. Cucumber juice also when applied on the acne spots helps in reducing the marks.
4. Apply sunscreen lotion on the spots and then after an hour rub lemon juice on it. Lemon is very effective in lightening the spots.