Hi and thanks for your question. It's a bit vague but somethings you can do o make any layered pas more interesting are to voice the chord differently amongst layers. Adding motion via usage of a mod wheel can give some life to a static pad as well. A trick I often use is to load about 6 sounds (ie, different pad sounds) and play one note of the chord on each. This goes the pad a much wider sound and creates a fat thick sound that you don't get just playing a chord on a pad. As for layering in general, the only suggestion I can offer via here is to find sounds that compliment one another. The blend should cover highs lows and mids. It's not possible to give you much more detail on how this is accomplished in writing. Good luck and let me know if any of this was helpful.
Buzz