Upon arrival, claim the Emerald in the pot close to you.
Continue on and kill the snake to the right. Ignore the lever for now since it is being guarded by a snake. Move a step forward and you will see two pots come into view. The one behind a plant holds a Twin Snake piece. The one above holds an emerald.
Head over the snake closest to you and kill it. Then make your way around the next closest snake to kill it. Hitting the lever causes the brown platform to move over. Making the lever accessible by allowing you to kill the snake. Do that and pull the lever to move the gray platform, serving up another snake for you to get rid of. Quickly take it out and head back to the lever you just pulled to return the gray platform to its previous position. Move over to the green lever to move the green platform so you can get rid of the snake and climb it to the next section.