Create a proper training environment. Think about how you would want to teach a small child. If they feel safe, calm, comfortable, and alert, they are more likely to take instruction effectively. The same is true for your parrot.
Find a quiet space where you and your avian student can focus on the task at hand. Choose somewhere familiar to the bird so it will already have a level of comfort before training starts.[1]
Don’t try to train when the parrot is overly agitated. Wait for a calmer moment. However, training with treats works best when the bird is hungry, so training before mealtime is usually the best scenario