In the summer hols we've promised our daughter she could die her hair -shes first getting it cut and donating it to a charity it's roughly 15inches king now so has grown the required amount then she wants it temporarily dyed . My worry is I've never dyed my self before so no idea what best brand to use is and also will it definitely wash out as 7 weeks later when school starts again I need her hair to be back to the blondey brown that it is
Any advice please