It's the same story no matter when you go. The park usually opens at 9am.
Be at the gate 15 minutes before 9am, they let you in to the first part, Go left to the ropes, national anthem plays at 9am, ropes drop. Walk quickly to the back of the park. Go on Kraken and JTA, in the afternoon, these rides have a 1 hour wait. Next go see the dolphin show, then the Clyde and Seamore show. It really doesn't matter what order you do things after that, as long as you get to each show 20 minutes before it starts.
There is a simulator ride near the front of the park leading to the polar bear exhibit. Skip the ride and do the terrain walk thru which will take you right to the polar bears. The ride usually has a long wait and is the kind of simulator that makes people sick.
Go feed the dolphins in the afternoon, feeding times are 2pm, 3pm and 5pm. Get in line before the fish food window opens and buy a few cups, they're $4 each.