It's exciting that you have a business idea and that it has brought you here looking for advice and some answers. First and foremost and my biggest and first advice is:
Don’t feel intimidated or think that you are way out of your depth. I know it can be overwhelming because I’ve personally been there and I did hire someone to help me write until I realized that I was constantly editing and fixing their work because who knows your idea better than you. Your more passionate than anyone who would write it for you. So don’t feel overwhelmed, you only need to plan it, which brings me to my next advice…
Make a checklist the checklist will help you organize your thoughts and give you a sense of achievement. Be sure to include main category and a list of things to do to cover and complete this category. But how do I know what should go on the checklist you ask?
Do some preliminary research (look for similar business plan to your desired industry) – I mean literary google search and type in the document type PDF or DOC “Business Plan for gym PDF” have a look at these documents and jot down the main categories addressed and develop your checklist as long as it feels relevant to you
Be sure to ask yourself “Who am I writing the Business plan for?”
based on the answer to this question you will be able to know how detailed or not you need to be, what kind of language to use, what do they care about most, the financial aspect? The idea itself? Etc. knowing all of this will help you focus and tailor your plan more to fit your audience and grant you a desired outcome.
The Financials: One of the most feared categories (or daunting to some) is the Financials and it is one the most important ones. Here is my tip for Financial Overview, it might look daunting and complicated for non financial professionals but you can simplify it by understanding 3 things:
a. Expense: What will be spending money on (fixed or rent or subscription, etc)
b. Revenue: how will I be making money (predict it for 1 year on a monthly basis)
c. Profit & Loss Statement = A – B
It’s a lot of fun to work on it once you get the hang of it. Mu advice is start doing it yourself, then bring in an expert to refine it for you, why? because going through the process yourself will give you a prospective and a dose of reality check of what your about to embark on.
I hope you find my advice helpful and I wish you the best of success <3