You should be very careful choosing skincare products and finding that perfect balance between excessive oil production and removing more protective oils than needed. That is why it is very important to use mild cleansers without harsh foaming elements and abrasive particles which deprive epidermis of its protection. This increases oil production.
After having washed your face gently, use a toner. Toners balance the skin's pH level after cleansing and contact with water. One of the functions of a moisturizer is to seal the moisture that has been on top of the skin inside. So you want to seal something nutritious for your skin instead of just tap water.
And yes, although you might think you can do without it, your oily skin still needs a moisturizer to keep it hydrated and to protect from the environment. Finish your simple morning/evening skincare routine with a moisturizer that has not only moisturizing but also nourishing and protective properties.