I don't know of better way than to let your business give you what you want for your lifestyle. Whether it's a sample business plan for a small business or one where your business gives you a plan, it should tell you what is needed to take you where you want to go and when and how you can get there and it should be in clear simple terms, supported with all the specifics. So using a sample business plan for a small business is just one of many ways to make a business plan but frankly I think designing one that will have your business give you exactly what you want is by far the best way.
Who is the ideal customer for this product or service? Really, ideas for business are a dime a dozen. You often hear people talk about a great business idea they have, but they rarely back it up with any kind of proof that a customer exists for such a product or service, and that that customer would be willing to pay. Try to be specific in profiling your buyer. For example, does your product or service cater to men or women, or both? What age groups or income levels does it service/attract? Are there any geographical areas that your product or service would supply?