Still, I believe it. The answer to your question is Business Plan Pro software. It can take a normal person step-by-step through the process, with guidance and examples, so that anybody who can run a business can develop a business plan. However, with or without Business Plan Pro, what you want is a good financial model that focuses on the way financials work, in the real world. You don´t have to have deep financial background or mathematical modeling skills if somebody who does sets the system up for you, and you estimate the assumptions. You estimate sales, then cost of sales, then personnel, then operating expenses. Each of these is a simple list, easy mathematics. Cash flow, unfortunately, is both critical to your business and not intuitive. With a good model, you can use simplifying assumptions to predict balances for money owed and money you owe, calculate inventory amounts, and predict the cash by working from balance sheet and profit and loss assumptions.
I’ve been doing business plans since 1974, for some big companies, for some very successful start-ups, and for my own company, which has grown from zero to 70% market share without outside investment. And the original ancestor of Business PLan Pro started as a set of templates in 1984. And it’s always been about doing good planning, for real businesses, from foundations I first learned as a Stanford MBA.
The real benefit is working the plan as it rolls into reality, checking plan vs. actual results, and using it to tune your forecast with actual results. It´s hard to forecast. This is a good reason to work with productized software, and not do it yourself. But then, as I said above, I´m biased.