If your secret is still in your head, you need to get it down on paper. This is so that your franchisee investors have something that they can use to replicate your business concept. Quite often we find people have written much of the business operations down but it only needs formatting.
However, we usually find that much work still needs to be done to produce a document that is professionally presented and can be used for training purposes.
The manuals written for your business become part of your intellectual property. This adds value to your business.
There are many aspects to your manuals and some companies have separate editions for certain elements dependent upon your particular business needs, for example, some businesses devote an entire manual to sales or marketing.