Well,you can't totally avoid it,they occur because of several reasons like : Hormonal change like getting your menstruation,lack of hygiene,stress and more.Anyway,you can prevent ior do something to lessen it,like trying home remedies,some acne new treatment like Baking Soda with a little lemon and more.
I suggest that you consult a dermatologist : http://www.nyccosmeticdermatology.com/

if you wash ,tone and moisturize you will have clear skin.that is what i do and i have no pimples

I'm not sure if this will make you acne free but it will help. I would say to wash your face with a cleanser for your skin type and to moisturize with a moisturizer that wont clog your pores. I personally tone my face with witch hazel but it may be drying for some skin types. Also try to keep your fingers and hair from your face amd wash your pillowcases and wipe your phone regularly. Also eat healthy by limiting your intake on sugar and processed foods like white bread. Exercise and drinking plenty of water is always helpful and helps your hair,skin and body. Acne treatments wih benzoyl peroxide work best for me but some people prefer salicic acid (?). Acne prevention is alot of trial and error and can be be frustration but as they say prevention is better than a cure(or someting like that lol) good luck :)

These are three things that work for me : ]
1] Boroline - has a high zinc content, kills bacteria.

2] Tea Tree Oil- Find it in pharmacies, also kills bacteria, top models use it,be careful not to get it near your eyes or mouth.

3]Wash your face once in the morning and once at night and apply moisturizer afterwards,to prevent bacteria build up.

Hope it works !!!!!!

You just have to keep your face clean and avoid putting your hands on your face. Avoid putting on too much make-up specially the ones with harsh ingredients. You may see Dr Schweiger or check out this website http://www.nyccosmeticdermatology.com/lipo-zeltiq.htm for a face that will capture hearts.

You may give your skin some gentle exfoliation by scrubbing it with products that are effective for oily sin. You can check out http://www.clearclinic.com/ for skin care ideas.