Stop Treating It Like A Hobby
It's All About Marketing
Have A Professional Looking Website
This is where you'll be housing your portfolio. You don't have to have any coding skills or necessarily hire someone to create a beautiful looking website as there are quite a few sites out there that make it as simple as dragging and dropping the elements you want to include in your website.
A few places to consider - SmugMug, SquareSpace, PhotoShelter, Zenfolio, Format, and 22slides.
Consider Hiring A Lawyer
... And You May Want To Consider An Accountant
Speaking Of Accountants...
Make sure to keep your personal and business accounts separate. This will make taxes way easier to deal with. Additionally if you end up working with an accountant, both you and they will be thankful for the separation.
Gearing Up For Business
Go Time
Now that you have some idea of what it takes to go pro, if you know that you will enjoy spending a majority of time on things other than photography, then it's time to do what you've been planning for - go and start your photography business.