To make a full head of hair a Mohawk without shaving your head

So, I’ve been trying to figure this out on my own. And I think I may be close, but I would like to get some info from other people who have done this or helped other do this.

My hair is trimmed all around. the back is cut to the shoulder . The rest is cut to the ear. All in layers.

I was thinking for st. Patrick day I would make a green Mohawk.

I was thinking pinning all my hair into a strait line along the top. Than spiking it and spraying it green. Would this work?

Or does anyone have a better idea?

Not involving shaving the sides.

Sorry for the bad sentences or confusion. English is not my first language.