Find your feet
Definition 1 of 1
Pro Tip 1/3New Beginnings
Used when starting something unfamiliar and gradually getting used to it. 
She's struggling now, but she'll find her feet at university soon.
Pro Tip 2/3Gaining Confidence
Implies a growth in confidence as one becomes more accustomed to the situation. 
After a few lessons, you will find your feet and play the piano with ease.
Pro Tip 3/3Time Factor
Suggests that the process of becoming comfortable can take some time. 
It might take a few weeks to find your feet in your new role.