Collect the 1st capsule that appears right in front of you by adjusting yourself slightly to the left and moving forward.

Turn 180 degrees and run in that direction, and you will see the 2nd capsule moving to the left on the ground. Collect it before it disappears under the mountain.

If you haven't already, turn to your left facing the mountain. Rocket boost over the mountain in this direction and you will land near the 3rd capsule on the other side.

Turn back towards the mountain and rocket boost up to the 4th capsule up on the mountain. Ideally, you want to land directly on the top of the mountain rather than the platform to save time.

Rocket boost off the mountain, facing the same direction you were coming from the 3rd capsule (on the ground) and you will land at the base of the mountain near the 5th and final capsule.