As an affiliate, you are a professional marketer, and need to come off as such. Affiliate networks will not approve someone they have never heard of applying with a gmail account. The first step to show that you are serious is to set up a small website and email account for the web address. This should be a more-or-less generic marketing site.

Use something like //themeforest.net to get going quickly. A two or three page site will be sufficient. If you know how to install and edit a wordpress theme, then I encourage a corporate theme. Otherwise you can go to fiverr.com or odesk.com and have someone set that up for you for $5-$30.