There’s a lot of place, not just galleries that I post to (Like Linkedin and soon Behance), but as a graphic designer I think I may have some sort of advantage because I did my own identity (Logo, business cards and such) without having to hire someone.
But you’re not obligated to hire a graphic designer, I think as a illustrator you can design quick business cards by yourself for you little publicity and for conventions and that will work for sure! Just as long you have your title (Illustrator, scultor, and ways to reach you. A pretty business card is also a plus!) Facebook and social media are a great way to extend your business, your family and friends can be your very first clients !
I’m going to repeat myself, but #6 is optional and you must be confortable to do requests before accepting them. They are good to boost your popularity / kindness towards your client base BUT they can also mean some people are going to wait for your request time instead of commission you directly. That’s also why you’ve gotta do requests in the style of quick doodles or sketches and keeping your complete work / bigger work for your commissions. But again, that’s my way to see it and you are free to do request the way you like it, as frequently as you like.
I am still opened to more asks about freelancing if you want.