You've been flung from the Colossus, and now you're in a diving pool. Swim to the surface and smash open the screen to your right. Welcome to the sexy God of War II minigame! Perform the Quicktime sequence to satisfy the pair of ladies and you'll be rewarded with plenty of red orbs.
Now get back into the pool and swim through to the next area, where you'll be able to climb a ladder to a platform and save. Pull the nearby lever and activate the grapple point and swing across. Climb the ledges and open the door to the next area, where there are more men to kill. Climb the ladder in here and the Colossus will stomp on you, so hammer Circle to throw him off. Now head left and grab the red orbs in the chest, and climb the wall on the left. Drop down and grab more red orbs, then get back on the wall and move up to the top.
IV. Boss fight - Colossus 2
Here, the Colossus will throw all sorts of arm attacks at you, so practise your dodge move. Wait for the Colossus to rest his arm on the side, andthen attack it with magic to cause maximum damage. After the third attack, he'll rest his arm on the side and you'll be able to climb it by pressing Circle.
Next, grapple to the other platform (on the right) and repeat the process. If you succeed, the Colossus will try and crush you, so press R1 and L1 alternately to escape and get yourself thrown free.