What materials would i need to put a single blue streak in my dark hair?

i have dark brown hair.

and i wanted one streak of aquamarine in my hair.

i have foils, 40 vollume, 20 volume, the color brush thingy.

i have to get the color obviously.

is there anything else i need?

any reccomendations?

What materials would i need to put a single blue streak in my dark hair?

you would probably need to get that streak area bleached before you dye it blue for it to show up