Sonic has returned for another adventure in the world normally inhabited by Mario. Kick off the fun by clicking through the menu screen and then choosing World 1-1.
Use the left and right arrows to move Sonic around. You can also use A to make him jump. Pressing S in conjunction with either arrow key will make him run.
Head to where the first two bad guys are walking. Jump on the evil turtle twice to send him away and then kick his shell into the other bad guy. You can jump on it a third time to stop the shell. Just make sure it doesn't hit you or you'll have to start over.