Early in your career you will be told you need to impress and gain a board sponsor. You do this by beating one of the Pro Challenges that appear when you are given this goal.
After continuing to gain respect as a skater for a while, the pro skater that you met to get in with that sponsor will send you a message saying you need to make a sponsor video. Complete the video challenge that you get after getting that message (all you have to do is get 2,500 in 30 sec, should be easy at this point). When that is completed, the first Pro board for that sponsor will unlock and you will get the achievement.