I spent a vast majority of my writing career editing, and I have seen my share of great and not-so-great ways to use dialog tags. Overall, it's all about balance. If you put a bunch of descriptive dialog tags in your writing, it becomes a major distraction.
If you get any one thing from this post, it's this: there is nothing wrong with the word SAID.
SAID is a great way to tag dialog. It's practically invisible and readers fly right over it without thinking twice. Using "said" helps your writing flow, and without consciously knowing it, readers appreciate it when writers use "said." It allows the reader to concentrate on the dialog and action of your story instead of trying to interpret cutsey tags.
Here's a couple examples of using descriptive dialog tags:
"You will die," he seethed.
"I quit," she sobbed. "Leave me alone."
"Oh please," he groaned.
What's wrong with these dialog tags? They actually don't make sense. Go ahead and groan. Did you actually groan any words? Try seething. How do you seethe words at all? Get rid of these. They are one of the first signs of amateur writing. Use of these descriptive tags is TELLING instead of SHOWING.
My favorite list of stupid dialog tags also include: hissed, spat, gasped, cajoled, snorted, moaned, and ejaculated.
So how can you show description and not use these goofy dialog tags? You can do a number of different things:
1) Drop the tag. If there's two people talking and it's obvious who's speaking, you don't always need dialog tags after every single block of dialog.
2) Use action. Example: His eyes narrowed. "You will die." BE CAREFUL! If you litter your dialog with all kinds of action, your book will read like stage direction for a play. I've made that mistake too many times to count. Action tags, if used properly, can be powerful. They can not only help the reader understand who's talking and show what's happening, they can give the reader some insight into your characters.
3) Use "said." It's tried and true. "Asked" is another great dialog tag that readers don't stumble over.
4) Use "said" with a little action. Example: "Oh please," he said with an exaggerated roll of his eyes.
What about alternative dialog tags?
These include: whispered, admitted, yelled, shouted, taunted, suggested, confessed, noted, examined, concluded, retorted, argued, questioned, offered, advised, etc.
Use these sparingly. They're not bad at all, and once in a while, it's good to put one in just to change things up a little. But just make sure it's not redundant.
Example: "I suggest you wear the blue one," he suggested.
Example: "Watch out for the tornado coming your way!" he screamed.
Both of these examples show redundancy. So tread carefully when using alternative tags.
And if you use the word "ejaculated" as a dialog tag, I will hunt you down and burn your manuscript.