Go to Level Up! after hit B (Xbox), then once you're done tutored of how to using the menu, scroll over to the right or left until you see Smith light up. Select that one, then accept the perk spend on the first one you entered.
What'the matter? Disliked my grammar? http://24.media.tumblr.com/tumblr_m5vz0vCbdS1r1g5kzo1_500.gif