hold tight
1. Literally, to grasp someone or something firmly. In this usage, a noun or pronoun can be used between "hold" and "tight." Please hold tight to my hand as we cross the street. My prom date held me tight as we swayed to the music. Betsy, hold tight to the string so the balloon doesn't blow away!
2. To wait patiently without taking any immediate action. I know you're anxious to hear how you did, but just hold tight—they'll let you know the results when they're ready. The CEO is urging investors to hold tight until the new product has had a chance to generate some sales.