Theres one simple and cheap way to keep acne at bay keep the skin surface clean. Wash your face twice a day or every time its dirty with pH balance soap. Besides neutral pH make sure theres a non comedogenic label on every skin product that you use. Scrubbing is not recommended when acne is still invading because it will only worsen the condition when skin is in healthy condition however scrubbing is also one of the ways to prevent acne.
Mild acne can be treated using topical medication that usually contains benzoyl peroxide (2%-5%), salicylic acid (1-2%), or retinoid acid(1-2%). Yet if you have sensitive skin , you should avoid using products with retinoid acid. Treatment by using the above kind of medication can be done continually up to 6-8 weeks. But chronic acne needs serious and professional medical treatment (dermatologist).