I'm not really sure how to be. Pretty much any object in your home can be used as enrichment for a bunch of species, for example. Anything added to an animal's environment is enrichment.
Indeed, even something like a new log on a climbing structure qualifies. Even sounds and smells of the neighboring species can be, as well as other novel sounds and smells. (Worth noting some sounds and smells are stressors rather than enrichment) For species trained as ambassadors, leaving their exhibits for a program or training session also often qualifies. The long and short is basically anything qualifies as long as it's positive for the animal (particularly in the respects of it doesn't stress the animal and cannot forseeably hurt the animal).
Because I don't feel like typing a lot today, here's some good links that break down what animal enrichment is: Animal Enrichment | Saint Louis Zoo Animal Enrichment Enrichment & Animal Welfare | Wild Welfare The Stimulating Science of Animal Enrichment - Untamed Science Animal Enrichment
Study about entichment for captive Ground hornbills : Investigating the Effect of Enrichment on the Behavior of Zoo-Housed Southern Ground Hornbills
