How to get rid of acne on the back and face?

Ive got mild acne on my back and face and want to get rid of it. I want to know what i should and shouldn't eat, what products i should use, and anything else that gets rid of acne in these areas.

Marigold Gel for Acne

Ingredients:
10 rose geranium flowers, with leaves and stems
8 marigold (Calendula officinalis) flowers
20 lavender flowerheads
200ml water
1 sachet vegetable gelatine
5 tsp vodka
20 drops tea tree oil

Instructions:
1. Roughly chop the flowers, leaves and stems of the rose geranium and place with the marigold flowers and lavender flowerheads in a large glass bowl.
2. Bring the water to the boil and pour it over the flowers to make an infusion. Leave to infuse for 10 minutes, or until the water has taken on the colour of the flowers. Place the infusion, including the plant material, into a blender and whiz. Strain the mixture through a piece of muslin into a clean bowl.
3. Now, in another bowl, dissolve the gelatine in 2 tbsp cold water. Gradually add the flower infusion, stirring to separate lumps. Add the vodka and tea tree oil, stirring until a gel is formed. Using a funnel, pour into a pot with a pump dispenser.

USE: Apply to affected areas 2 times a day, or as frequently as needed.
STORAGE: Keeps in the refrigerator for up to 6 weeks.