First of make it yourself, if you are keen on Martinez analyse his formation and see what his players do and match it up. I'm a massive fan of his work. He usually goes with a 4-2-3-1 formation, playing with two wingers attacking. The two centre mids are the key build up through progression up the field. This allows the right and left back to have the creative freedom and that's how it works. CM's I'd say are the most vital part of the formation.