Make it STUPID SIMPLE
When introducing new toy items, it is useful to start VERY EASY. This is so your bird CANNOT FAIL.
If you start so easy that the success is guaranteed, then your bird is likely to have a positive association with that enrichment and try it again in the future.
Start so easy at first that it's kind of silly. Food in open cups. Then increase the difficulty slowly, making sure success happens quickly and easily at each step.
Never push your bird to the point of frustration. Especially at the beginning, frustration is a de-motivator. Building resiliance is done over time.
Picture: Here you see a Quaker parrot infront of some muffin cups on a skewer. A blueberry can be seen easily acceisble from the bottom most cup.
Picture: dish of crumpled cups. Only once your bird is able to succeed with open cups can you start to crinkle them.