How does one dye only the grey area about an inch thats grown as the rest of your hair is still dyed

after dying your hair on your head. it grows and after a couple of weeks you see the new hairs which are still grey what do we use instead of having to buy a complete dye pack again. we only need to touch up the new hairs.

How does one dye only the grey area about an inch thats grown as the rest of your hair is still dyed.?

There is a new product out available at all drugstores, I think by Clairol, that is strictly for touchups on roots between colorings. Although, it is not recommended that you touch up roots until 4 weeks because even if you're very careful some color will still get on the hair shaft. This makes hair over processed and damaged and can break it off.

How does one dye only the grey area about an inch thats grown as the rest of your hair is still dyed.?

it's called a touch up. only dye the gray. use a dye brush.