I strongly suggest that would-be entrepreneurs do a business plan. As a result of completing the plan you will be much better prepared and know whether or not your business idea is feasible. Try the following article for a short-cut. However, I caution you on following a short-cut unless you have substantial experience or knowledge about your area. Proceed with caution without a business plan!
How is your business unique, and why will your goods or services appeal to customers? What are the primary differences between your company and your competitors? What are the driving factors to choose your business over another?