Show don't tell

I was reading a book I've read a dozen times. This is what I gleaned from it.
Those lovely, delightfully descriptive adjectives and adverbs that we merrily sprinkle throughout our profoundly, singularly distinct writing. In a word, DON'T.
Remember writing essays in high school? Take whatever you are working on, look for words ending with ly, and change the sentence to give an example. Which sounds better.
I hate you, the boy angrily yelled at his mom. Or The boy threw his clothes unfolded into his backpack, stomped to the door, and slammed it on his way out. I hate you, was the last words she heard.
If you take nothing else from high school English class, remember the words, "for example".
One half to three fourths of your tag lines should be he said, or she said. If you have two people, or a group with distinctive voices, written so you can tell who's speaking, you should be able to have no tag line at all.
Find your favorite book. The one you have practically memorized so you won't get caught up into what happens next. Look at the dialogue. Watch for times when an action shows tone of voice.
Which makes a better experience:
"Come to my room", she whispered huskily. -or-
Fatima wrapped her scarf around my neck. Drawing a well manicured finger down my bare chest, she said for my ears alone, "Come, let's leave the party"