It's too simple for her to need an accountant, particularly as I expect that she is numerate.
All she needs is a simple record of how much she takes in (a pocket diary might suit) and a note of anything she spends (e.g. travel if it arises, a reasonable estimate of the cost of heating a room if she takes students in her own home, purchase of textbooks or stationery).
When she sends in her form 12, she can submit a supplementary sheet showing how much she took in and spent. Once the tax official recovers from the shock of seeing such voluntary disclosure the wheels will be set in motion and everything will be sorted for her.