Oily skin contributes to acne
simply because the over active oil glands in the skin produce secretions which clog the pores, leading to acne. As you search for methods to reduce oiliness, make sure that you don't use things that excessively dry out the skin (for example, some people apply rubbing alcohol to their face); excessive dryness can actually case the oil glands to become stimulated and produce even more oil.
There are several common sense approaches that are absolutely essential. For example, minimizing the use of cosmetics is essential to keeping the skin clean and clear. Additionally, using an antibacterial soap will keep down the bacteria which tend to make the acne more reddened and inflamed.
After these simple steps, I generally recommend a comedonolytic acne cream either containing benzoyl peroxide or salicyclic acid.
If these do not work, then you will need to see your primary care doctor
or your dermatologist
in order to get a prescription strength medication. Accutane is very effective, but this is sort of the last line treatment when all else fails. There are numerous other prescription strength creams and ointments that can be tried before Accutane that are also very effective and have many fewer side effects.