The avatar is going to be defined by your ideal customer. Your ideal customer needs to be defined by:

-The market they are serving
-Business size -- solo entrepreneur, 3-5 employees, 10+ employees. etc.
-Specify the service that you want to provide: web site design, logo design, offline brochures, etc.

Always, always narrow down as far as you can and then build from there. You never want to be the business that says: 'We specialize in everything' Because we all know that this means you are not any good at anything.

I am not sure if you are even sure yet what you want to offer never mind who you want to offer it to, but here's a quick thought:

If I was a web designer looking for clients I would niche down to a tight niche, then determine the avatar of my ideal client and then find where they are -- finding them is easy once you know who they are. ;)

Example: Web design -> WordPress-> Mobile responsive -> Chiropractors

This is still really vague and based on not knowing you or your business at all, but hopefully it will at least get you unstuck enough to keep moving ahead.

Let me know if I can help further.

Thanks.