It makes sense to prepare a business plan early and save some of the income.
Not only because it is good to have a cushion in bad times, but also to take a break or a vacation in between.
Since you never know what the future holds, it is important in the long term to put something on the high edge and, if necessary, to invest or invest. So far, there is no business plan for sex workers, but you can start by keeping a cash book and have an overview of ongoing costs and income.
Since there are no business plans for sex workers yet, it can be compared with other self-employed entrepreneurs / small business owners who build up reserves for worse times. There are samples of this on the Internet. There is a rule of thumb: ⅓ taxes, ⅓ living costs, ⅓ saving, you can drive well with it.