1. Crouch precariously close to the edge of the platform.
2. Point your eye-lasers at the 2" space next to the train. Be sure to stand directly in front of the doors while doing this.
3. Concentrate. Try to ignore the huge, yellow beam of light shining directly on your head.
4. With your eye-lasers, create a single red bubble.
5. Board the train. Act as if eye-lasers and large red bubbles are perfectly normal.
(from the San Francisco BART)