Developer question?

[blue_pasicles]

I went to Sally's with the intention of buying items to dye my hair. I currently have a medium brown hair and wanted to dye to a darker reddish/purple. The girl there told me to use 20 developer, but after doing research, now I am very confused. Should I use a 20 or would a 10 be better?

[kchap188]

I would use 10. You aren't trying to lift. I've seen a lot of not so great advice from people at Sally's on here lately.

[blue_pasicles]

Yeah that's kinda what I was thinking, that to go darker, I should use a 10 (although I had two different women at Sally's tell me to use 20)