How do you do your hair like an anime character?

Like this~

The only advice I can give is to get it cut in layers, and maybe straighten it, since most anime characters have straight hair.

But why don't you take a look at your favorite anime characters, and see what hairstyle you like best? You can try to copy whatever hairstyle looks nice to you, maybe you'll like it. ^^

Have it like sasukes if your a boy

Since you don't want to dye your hair and it is long you could go for Homura Akemi from Puella Madoka Magica. (best choice in my opinion) picture below

or

Saya Minatsuki from Black Cat(she has dark brown/black hair)

Mato Kuroi from Black Rock Shooter(has blue tint but not much)

Yomi Takanashi from Black Rock Shooter(tint of brown)

well i went to the cherry blossom festival once and had a similar problem but we also decided to go with someone simple like sailor moon. her hair is pretty easy so there is one suggestion or you could do someone like this person in the picture where you could just easily do the hair style by just looking at the picture.

Even though you think it's impossible to believe,but it's true....my hair is exactly like Mouri Ran from Detective Conan....