The biggest difference between blogging and legal writing is that blogs are usually written in a more conversational tone. If your goal is to attract new clients and appeal to as broad an audience as possible, then you have to assume that readers don’t have a basic understanding of law. You can write conversationally while still demonstrating your expertise.
Online readers are often looking for something they can quickly digest. This means that blog posts should be scannable, containing ample white space not bogged down by huge blocks of legal jargon.
And finally, footnotes are not necessary when writing law blog posts. The standard practice is to use hyperlinks to reference sources.