Hi lauriet, the practitioner asks you before you start treatment if you want the colour to match your sides exactly or if you would like the top to be slightly darker, it’s up to you, they always start of on session 1 a bit too light then they go a bit darker on session 2, then if you want you can go even darker on session 3, as long as it’s blended well into your own hair you can go a few shades darker than your existing hair, hope that helps