UK Girls: Need hair dye advice.

I’ve been getting my hair dyed for years at a salon and love the colour, but can’t afford the £60 a month it is costing. I’m thinking about moving to home hair dye. I need your tips! I have black hair with a bit of grey - I want to go a mid brown colour - sort of aishwarya rai colour. So ladies, what colours and brands have you tried and what would you recommend?