You have your idea: the "what" and the "why" - you aren't ready to build yet though. You may need to work in reverse to how you would assume:
1. Reporting: Create a report showing your revenue figures, customer base (including demographic) and other relevant business information. Everything you enter will be estimates of course - but as you gain validated feedback, you can adjust these estimates and always have a clear, real-time picture of your business's outlook.
2. Marketing: Never start building unless you have a customer base. Show your idea to a range people and find out if they would buy it and why. What you need to properly present this idea is up to you, but a couple of good options are a mockup in PowerPoint, PopApp or a video.
3. Release: Make a website, contact news publications and start taking orders - this will give you a hard deadline to deliver the product.
Now you can start building, and with the confidence (and pressure) that there is an audience waiting for your product.