Skater Game - Main Character Creation

I want to develop Skate game like Skater Boy

How to design main character?

At present I think that I have to attach two collider to my main character.
One is box collider and other is sphere collider.
Sphere collider places at bottom and box collider placed at middle.

I think this type of structure because of smooth character movement.
So please guide me on this.

I know that I am asking pretty broad question but I want some suggestions from your side.
Thanks for your attention.

Unity’s new standard assets has a great 2D character controller. I think that’s a great place to start. Take a look at how that character moves, you might even replace some textures.

Unity has published 2D character tutorials as well:
2D Character Controllers