Please help me if you can!

I’m writing a memoir I just need to know if this simile makes sense. If not please give me a better one :) !

“Good morning Devy, hang up your bookbag and have a seat.” Mrs. Jane said. Her tone always soft enough to lay on making us feel at home.


^^^ the last sentence is the simile. I just need some sort of good figurative language there because this is going to be restated as an ironic statement at the end of the story.