A boosted profile means that your HER profile will appear at the top of the meet section for one hour. This is a one time cost of $5.99. 

To access boost you can either go to your settings where it will appear at the very top of your settings menu or wait for the in app prompt to appear. 

Non-Premium User View                                               Premium User View

Once you have completed the purchase, your boost mode will be activated and there will be a glowing outline around the profiles in the meet section. Once your hour is up, the glow will disappear.