Take it from someone who writes for a living: Just start writing. Your first idea is probably not going to be a winner, and that’s why you should get it out of the way as soon as possible. Write out all of the ideas you have for your copy, no matter how silly– you may be surprised at what gems come out of a brainstorming session where you don’t edit or criticize your creativity.
Read Joe Pulizzi's excellent book Epic Content Marketing. I started reading it after I wrote this post and it confirmed and expanded what I already knew about content marketing, with much more detail than I could ever go into here. Something Pulizzi emphasizes which I originally left out was the importance of focusing on producing mobile-friendly content, since smartphones are becoming the dominant way in which most of our customers access content. Also read Michael Hyatt's Platform, mentioned above. Frequent websites like those of Content Marketing Institute, Ragan, Copyblogger, Michael Hyatt, and Gary Vaynerchuk and sign up for their email newsletters. It won't take you long to become not just familiar with content marketing, but an expert.
Let’s be honest– copywriting can be scary. Even for seasoned writers with nothing to prove, writing advertisements or marketing content can be daunting and terrifying. Copywriting is the literary equivalent of climbing Mount Everest, if you can imagine Mount Everest covered in junk mail and sales papers. You know it can be done, you’ve seen it done well, but you’ve also seen a lot of people die trying and you don’t want to be one of those fatalities.