Be bursting to do something
Definition 1 of 1
Pro Tip 1/3Emotional Intensity
Suggests a strong feeling where you can hardly wait to act. 
He was bursting to run to the stage when his name was called.
Pro Tip 2/3Informal Usage
Best used in casual conversation, not formal settings. 
At the party, Mia was bursting to show off her new dance moves.
Pro Tip 3/3Strong Desire
Implies a personal, often irresistible desire or need to do something. 
After the exam, Jamie was bursting to go on vacation.