You can use this layout openly with out a focus on the meanings of the three cards. Meaning instead of using the typical (Past, Present, Future) or (Physical, Emotional, Mental)..... You can simply state your question or intention and read the energy of the three cards together.
Past, Present & Future:
Simple enough allow the cards to be placed in their spot and then read from the past into the future, the cards should connect to one another and pattern out something that is coming into your field. Past may come up for you to review in order to move forward into the future.
Physical, Emotional & Mental:
This layout can be used to get a gimps at your energetic field and see what is floating around either for you to review, learn from and eliminate or grow. This can also indicate illnesses coming into the picture, or even guides hanging around. This can also show the direct energy of the fields. Use a forth card at the end to see what the message from your Spiritual body is.