Okay ladies please help me with these tantrums 🙈

I have a 20 month old who is throwing MANY tantrums lately. Like she will scream so hard and roll on the floor to the point where she starts choking on her screams. It will be over very minute things, even when she’s well rested. I know tantrums are normal... but I need help on how to handle them. So far I’ve been sternly but calmly told her that I will not listen to her until she has calmed down and that she needs to be nice.

It’s really hurting my 6 months old’s nap schedule. My 20 month old will scream and cry so loud that it’s impossible for my other babe to sleep and it’s frequent. Even with a sound machine!

So please, any advice on how to handle the tantrums so she begins to learn this behavior is not okay?