I have written many business plans. Most were never followed! So was it a waste of time? Absolutely not. A business plan should be a living document not a static document. I’ve see people pay big money for a business plan, use software to produce one and I have seen people just start writing by the seat of their pants. Business plans have many purposes, the most important one is for you to determine if your idea is viable. Of course viability depends on the assumptions you make for revenue and expenses. Be conservative, ask for help. There are a lot of resources in this area. Although every business plan is different they all must have certain components. You may need a business plan for an SBA loan or to show potential lenders, vendors, or prospective employees. In each case the requirements will vary.
Every business plan will contain an executive summary which is about three pages that describes what you are doing, who is doing it, the target market and why there is a need. You will need bio’s on the major players if not just yourself, an income statement, a balance sheet and marketing plan. The income statement should list all your expected expenses and initial expenditures as well as the revenues and how soon you will have x number of customers. Understand that all of your assumptions will be wrong. The object is to have a starting point, not to predict the future. You must also have a competitive matrix and some threat analysis on what could cause major problems. We have samples if you need them. Make sure you have three or more people read it for content and typos.