I just used an old shampoo bottle (housemates still use it). I funnelled in a tub of sodium bicarbonate and added water until it was just runny. 300ml bottle la

I just used an old shampoo bottle (housemates still use it). I funnelled in a tub of sodium bicarbonate and added water until it was just runny. 300ml bottle lasts me ~8 months, using about 3 times every 2 weeks. Cost to me: about £3 / year. Hair quality: great. I used to pretend I didn't care, but I do and this works and I'm never going back to shampoo.