Lava Mountain: Zone 2
Red Star Ring 1: During the side-scrolling sequence at the beginning of the level, you'll need to jump across three circular railways in a row. The first Red Star Ring is resting on the third.
Red Star Ring 2: When the game switches back to a 3D perspective again for the first time, a couple of flying enemies will begin dropping bombs on you. Keep to the rightmost rail to hit a jump pad that will launch you to the next Red Star Ring.
Red Star Ring 3: During the second side-scrolling sequence, after jumping a number of bomb carts, you'll need to jump a couple of gaps by chaining attacks on several groups of blue insects. Shortly after, you'll come to a large dip. The Red Star Ring is situated on an elevated platform. You'll miss it if you stick to the main path, so jump from the rail midway through the incline.
Red Star Ring 4: Near the end of the second side-scrolling sequence, you'll come to another set of circular railways. There's a Red Star Ring on the large one, trailing behind one of the bomb carts. Time your jumps in such a way that you can immediately leap off after snagging it, as hitting the bomb cart will result in instant death.
Red Star Ring 5: When you come to the final stretch, you'll pass through an area in which you'll collect numbered rings while large doors close. As you're exiting the room, stay on the green rail opposite the "1" ring. This will take you to the final Red Star Ring.