Balance passive tasks with group work. A noisy class often develops after long periods of passive activity.
I know that sounds like telling you to suck eggs. But I have known some to teach from the front all day long. I've done it before. You teach - the kids work.
Fairly passive learning. A full day of it and groooooan!
I hang my head in shame. But I'm a lot wiser now. Mind you it has taken my 40 years.
Students often get chatty after prolonged periods of passive activity.
Solution: Balance these passive periods with active periods. Active doesn't just mean jumping around. It can mean that your progress from a listening activity to talking activity.
Instead of hands up to answer, tell the kids to give their answer to their partner. You can allocate them and A and B and then have A tell B etc.
I find that a pain but others can do it well. I just tell the students to share with their partner and let them work out who does the talking.