Put your best foot forward
Definition 1 of 2
Pro Tip 1/3Positive Impression
Use it when you want to impress someone, like a boss or teacher. 
I've got to put my best foot forward during the presentation.
Pro Tip 2/3Job Interviews
Especially useful in job interviews to show you're an ideal candidate. 
I need to put my best foot forward for this dream job interview.
Pro Tip 3/3First Encounters
Important in new situations where first impressions count. 
Meeting her parents, I really have to put my best foot forward.