How Do i put highlights in my hair?? 10 POINTS?

Hey ppl .. iv'e been thinking if i buy those packets of hairdye in a box... and put foil on certain parts of hair and only spread the dye on certain parts... would that b the same as they do it in the hairdressers...? or they use a diff mixture for highlights?? will my idea work.. so i can just do it athome?? thx