The most difficult thing about a tax return is that you do not know which tools or clothing can be tax deducted.
This is often a matter of discretion for the responsible tax officer. But you should try it. Help is available from tax advisors who are familiar with prostitution. Ask your nearest advice center whether they know addresses of tax advisors that are recommended or look at the list of addresses of the professional association BesD. One-off advice can be very helpful, even if you can make your tax return yourself.