give somebody a hand
give (someone or something) a hand
1. To help someone with something. I hope that someone will give me a hand with these bags—there's no way I'll make it to the fifth floor on my own! No, Billy can't babysit, he's giving me a hand with my car today.
2. To applaud someone or something. Wasn't that a great performance? Let's give them a hand, ladies and gentlemen!