I'm an experienced secondary English teacher. I currently work 0.6 and have expressed an interest to my headteacher in increasing my hours to 0.8, but they can't currently afford this. I'm therefore seriously considering doing some tutoring and I'd be keen to hear from anyone who's done this.
I'd offer KS3, GCSE and A Level, English Language and Lit. We are on the border of a grammar area but I'd need to gen up on 11+ before offering this. I'm an Oxford graduate so could potentially offer Oxbridge entrance too. The going rate around here (affluent part of the West Midlands) seems to be approx £25 / hour for KS3, £30 for KS4 and 5. I have a current DBS and already do a tax return so would declare the earnings that way. I need to double-check my contract in terms of informing school - we are asked annually to complete a declaration of interests so I would declare it there. I wouldn't tutor pupils at my school in case of an ethical conflict.
There seem to be a lot of local tutors on Tutor Hunt and First Tutors - did you sign up with any of these? There are several active local Facebook parents' groups where I could hawk my services. Do you see students in their homes or in yours?