Disclaimer: Although I am an attorney, I am not licensed in the state of Georgia. Thus, I am not qualified to provide you with legal advice or counsel. Consider what I post here as nothing more than points to double check with an attorney licensed to practice law in your home state.
Here's a few preliminary things to consider:
1) I notice that you own your own small business. Do you operate as an incorporated entity, i.e., a corporation, LLC, etc.? I ask because this may determine whether you may proceed by representing yourself, or whether you must retain an attorney to represent your company. Small claims court is typically devised to allow parties to proceed without the need for attorneys. Rules of procedure and evidence tend to be simplified in hopes of achieving a fast resolution. Although trial by jury is usually available, for a higher fee, most small claims actions are determined by a bench trial - a trial conducted by a judge who determines the ultimate outcome of the case. However, almost every state requires that incorporated entities be represented in any court, including small claims, by an attorney. Now, in my own practice, I've seen incorporated parties squeak by this rule, usually because the court didn't bother to enforce the rule and/or because an opposing party didn't make appropriate objections. Still, be aware of this preliminary issue.
2) As the plaintiff, you'll have the burden of proof to prove how and why you are owed money, and in what amount. For a civil case, that means you'll need some way to prove that your story is more likely true than not (civil claims, such as this breach of contract action, typically mean a lower standard of proof is required, "preponderance of the evidence," which translates to being more believable than the other guy.) If you have any type of written contract, of course, that will help your cause greatly. HOWEVER, oral contracts ("parol agreements" in lawyer lingo) are every bit as enforceable, if you can prove or demonstrate what the terms of your agreement were. In your case, it sounds like you have a previous course of dealings whereby you'd provide some sort of service at the request of the other party, and then they'd pay you for rendering that service. If it were my case to prove, I'd begin my case by demonstrating that previous course of conduct - describe or prove as best you can what you did for the defendant, and then prove they paid you for it - bring in bank statements, copies of cancelled checks or stubs, invoices, bids or whatever else you have to prove that you've done stuff for the defendant, and the defendant would pay you for it. Once I have that groundwork down, I'd go through what work they requested of you, then what work you performed, and then cover what your fees for the service would be. If applicable, I'd also go through any demands you made for payment, notices, invoices, etc., and also cover any rejections, refusals, or denials of payment, as the case may be.
Of course, bring anything else that is relevant to the dispute, especially if it's some sort of tangible evidence. If you have something in a text message or an email, try to get a printout. Most cell phone service providers will, if subpoenaed, provide authenticated printouts of text communications, and you can usually issue a subpoena even if you are bringing a small claims action.
Now, let's say you've won your case. Collection can be a more difficult proposition. As far as I know, each state has remedies you can use to attempt to levy against a judgment debtor's assets after you win your case. This can include judgment liens on real property, and the garnishment of wages, other income, personal property, and/or bank accounts.
Another avenue you may want to consider, if applicable, is availing yourself of a mechanic's lien. I don't know if the work you did and your situation would make a mechanic's lien useable, but it's another resource to explore.
Best of luck to you.