Instructions
Adjust Kratos' hand with the right controller as soon as the controller prompt displays on the left side of the screen, just moments after Helios begins to blind you. It can be very difficult to spot Kratos' hand because of the intensity of the light, but if you move the control stick up, down, left and right you'll see the outline of his hand and its shadow, and that way you can move it closer to the light's source and block it. If you take too long, Kratos will be forced backwards and will eventually die.
Press the left control stick to move Kratos forward immediately when Helios' light is blocked. You'll know when his light is blocked because instead of seeing almost nothing but white on the screen, you'll see Kratos much better as well as the environment around him. Kratos cannot move forward while he's blinded.
Watch Kratos' hand and make adjustments as necessary. His hand will begin to move and stop blocking Helios' light, so you'll have to move it back into place. Kratos may be forced to stop once or twice, but that's fine; as long as you get his hand to block the light within a few seconds, you'll make it to Helios.
Continue advancing with the left control stick and moving Kratos' hand with the right control stick to reach Helios.