(Huge hat tip to Joanne Harris on twitter for starting a thread on this, which happened to be something I was planning on addressing anyway. She gave me the idea on just how to break it down and do the thing.)

I’ve recently had a few edits that were bogged down by an overuse of dialogue tags and they were all the same:

“(name) said (adverb here).” So, for example, “Susan said angrily.”

I realized… dialogue tags are a bit of a bear, aren’t they?

Generally, there are two camps:

1. Only use “said” and never anything else, because it distracts from what the person is saying/the narrative otherwise.

2. He said/she said can feel dull and repetitive if that’s all the author uses, so shake it up with words like whispered, shouted, etc. It will keep things from feeling monotonous and engage the reader.

No matter which camp you fall into (I really don’t care. I think both have strengths and weaknesses, but the author needs to make a CHOICE and I won’t generally interfere with that choice aside from editing stuff), dialogue tags can be a bit hard to manage and they can get out of control pretty fast. So, here are some things to be aware of.

• Read the dialogue you’re writing out loud. A lot of the time, you’ll realize what you thought needed a tag, might not after all. Or maybe if there isn’t a tag, you’ll realize you need one there. Usually, if you read out loud, things tend to shift, though. You’ll “hear” the conversation, and it will also allow you to hear where the tags could be best used.
• Remember there are other ways to indicate who is speaking. Action beats can be hugely important in dialogue scenes. You can “show” that someone is speaking without using a dialogue tag by inserting an action beat.
• People multitask. You don’t always just sit there and talk, right? I have long, evolved conversations with my kids when I’m cooking, for example. Consider layering in a conversation while your characters are doing other things. This will show your characters in different situations, which makes them and your conversation both a bit more interesting.
• Consider your dialogue. If, for the meaning to get across fully, you need to tell your readers how the line is delivered as well as what the line says, you’ll probably need something a bit more informative than “s/he said.”
• One thing I run across a lot is repetitive information. If it’s already clear how someone is delivering their lines, you don’t need to restate that in the dialogue tag. For example, if it’s clear that Maurice is crying, you don’t need to add “he cried” in the dialogue tag. We don’t need that information twice.
• Be careful in scenes with only two people speaking. You don’t need a tag on every line. Similarly, in a scene with more than two people, give your readers enough information to allow them to know who is speaking, and who they are speaking to, but don’t bog it down with a dialogue tag on every line. Remember, action beats, etc. can be just as powerful informational tags as “s/he said”.
• I always suggest reading out loud for everyone, always, but if you aren’t an author who does that, I highly advocate you start to do so at least in scenes where you have a character with a specific speaking mannerism. This will help you “hear” how they sound, so you’ll know if you’re laying it on too thick (which can feel campy or unbelievable) or if you need to push into that a bit harder.
• A lot of people poo-poo adverbs*, and I am not a huge fan, but I think it’s really the verb-adverb relationship that can be a bit of a bear in tags (all the time, really, but let’s focus on tags). There are some strong adverbs. “He smiled sadly” is one I’d argue is a strong adverb choice, because it changes the meaning of the sentence, whereas “He smiled happily” is a weak one, because “happily” is implied in the act of “he smiled”. If you fall into the trap of using a lot of adverbs in your dialogue tags, stop and ask yourself how you can strengthen the verb, which might ultimately make the adverb unnecessary. So, “he said loudly” can move to “he shouted”. I’d argue that even if you’re in the “always use said” camp, “he shouted” is a much stronger alternative than “he said loudly.”
• I’m not a fan of emotion words, as I call them, unless they are carefully and purposefully used for maximum impact. So, I’ll generally always edit dialogue tags that say something like, “he said angrily”. Reason being, it’s fine to tell me he’s angry, but it will mean more to me if I’m so immersed in the scene, I can infer his anger through actions and cues, through information you give me rather than things you tell me. “He’s angry” is fine. If you SHOW me his anger, I’m interested. More, I’m invested. Think of “emotion words” as a Bandaid… a placeholder. The second you fall into the “(name) said (emotion-ly)” trap, ask yourself how you can infer that emotion clearly without telling your readers what it is. Your scene, dialogue, and readers will thank you for it.
  
  IE: Don’t tell me he’s angry. Layer that anger so deeply into your scene, it’s present even when you don’t explicitly say so.
• Lastly, I run across this a lot:
  “Go awa—” This is when someone’s speech is cut off abruptly.
  “Go away…” This is when someone’s voice trails off.
  
  The action, either trailing off or being cut off, is given to the reader in the grammar used, either an em dash or ellipses. You do not need to reiterate what is happening here. So, for example, “Go away…” her voice trailed off. You don’t need “her voice trailed off” because that’s implied in the use of “…”. Similarly, “Go away—” she cut off. The “she cut off” is implied in the “—”.

And that’s all I’ve got for now!

(A note on adverbs. Adverbs within dialogue are a different beast entirely, because that’s how people talk. It’s when we are not in dialogue, rather working outside of dialogue, where use of them needs to be careful, deliberate, and moderated for maximum impact.)