Here's my experience from investigating this:
First, the laws. You generally cannot make money offering financial advice without meeting various state-specific requirements. I think this usually involves passing some tests like the Series 65, which covers lots of investing topics to show you know what you're doing. A small wrinkle in the process is that the Series 65 covers lots of aspects of daytrading that a Mustachian has no need to know, like options and futures trading. There's no reason you can't learn all of this, though. When I added up everything I computed a total startup cost of about $200-300 plus a month or so of studying.
The next problem has been much more vexing. When I try to help people I know with their investments I run into this frequently. People are already getting help from a "financial advisor" who is really only a broker making commissions off their recommendations. These people continue to use this broker, though, because they are making emotional decisions about their money and "trust" this person who "takes time to listens to them." I'm trying to be a teacher, but my "clients" are looking for a salesperson to give them a hot fund and stop asking lots of tough questions like how high their expenses are. So if you want to be successful in this field, it's not about how much you know about investing. It's about soft skills and sales tactics.
Take a look at this to get a glimpse of your competition, and how even government financial investigators can get fooled.
http://www.cbsnews.com/news/retail-financial-advisors-looking-out-for-themselves/I'm starting to come around to the idea that trying to be a Mustachian financial advisor is a lot like trying to be a social worker helping the homeless. If you have the patience, empathy, and ability to disconnect that the latter field requires to try helping people who have no interest in helping themselves, you could be successful.