Marketing to the Federal or for that matter any level of government is not what it is in the commercial side. 

Having a Capability Statement is one way to inform government and prime contractors who you are and what you do. 

Be professional, don't use a gmail, yahoo or aol account. 

Have a website, for very little you can have a professional website up and running in a day.  GoDaddy and Wix are just two of a entire group of online site providers.