Just used a semi dye brown on my hair yesterday. I’m happy enough with the colour, although it’s a bit warm & I know after a couple of washes it will have washed up & look even more of a warm brown. I really want an ashier tone and I don’t want to have to dye it again with an ash based colour dye so I’m thinking of trying a blue shampoo first? Will that help? There’s so many, which one is good & will do the trick?