Just start right away with washing twice every week. After a few weeks, your scalp has adjusted to shampooing less frequently and will not get oily that quickly. Sulfates (the main ingredient in shampoos, dishwashing liquid, etc) are aggressive cleansers and completely freak out your natural oil balance. Washing every day with shampoo is REALLY bad.
Current length: tailbone
Goal length: mid-thigh (wet)
3A/2C M iii med por, high elast
It all depends on your hair. I still cleanse almost daily because I do several hours of martial arts after work. I don't normally use sulfate shampoo, although I do use one on occasion. I normally rotate between sulfate-free shampoos, cleansing conditioners and straight co-washing. You can try a dry shampoo to touch up oily roots between shampoos if you want to try going a day or more between washing.
3a/f/iii Modified CG since 11/5/11 CLEANSE: VO5 Vanilla Mint Tea Clarifying, DevaCare No-Poo, CHS Treatment Shampoo RO: DevaCare One Condition, SS Caitlin's Conditioner, Mop Top Daily Conditioner LI: SS Repairing Protein Treatment, CHS Silk Leave-In STYLE: Re:Coil, Curl Keeper, Deva Ultra Defining Gel, Curls Rock Amplifier and Strong Hold Mousse, Sweet Curls Elixirs Okra Gel and Hard Hold Gel, SS Curl Enhancing Jelly and Firm Hold Gel