Many fiction writers have difficulty using tags when they first start writing fiction. So before your write, it's a good idea to learn the ins an outs of tags.
First of all, what is a tag? It's the "he said" or "she said" that follows dialogue to tell the reader who is speaking.
Second, what is the misuse of a tag? Everything that is not "he said" or "she said."
Many beginning and some experienced writers use tags to do everything from describe eye color to moving the character across the room. Examples:
"I'm cute," she said, winking at him and obscuring one perfectly periwinkle blue eye.
Or how about...
"See you later," Sam threw over his shoulder as he sped to the door.
Current terminology is too much information. That certainly applies here. Don't take short cuts and use tags for anything but what they were intended. Here are some things to keep in mind when using tags.
1. Always state the person's name or the pronoun first and then the "said." It's just awkward to use "said" first. You would never say "ran she" or even "sang she," so why would we say "said she." Instead, it is "she ran" or "she sang." Basically, your rule of communication applies here. Tags are merely utilitarian. They tell you who is speaking. Don't try to make more of them.
2. Stick to "said" or other forms of it, such as "whispered," but don't use words that aren't even a form of speech, such as "giggled" and "guffawed." I'm not even sure what a guffaw is. I suppose it's some sort of snort, but I know for sure that it's almost impossible to speak while giggling, guffawing, or snorting, so don't use them as tags.
3. Stick to "said" and other forms of it even when the tag you are choosing is a form of speech. For example, it is reasonable to argue that "responded" could be a tag. Theoretically, it could be speech. It's just better to stick with "said" as it will keep the reader on track and won't take away from the real meat of your story.
4. Don't use tags to do the work that you, as a good writer, should do. You should always show the reader what is happening not tell them. Therefore, don't use your tags to tell the reader what is happening in your story. For example, don't write:
"John I hate you," she said while throwing the chair at him and hitting the mirror on the wall.
Sarah picked up the chair and threw it at John. It struck the mirror and both crashed to the floor. "I hate you," she said.
Get the point? You, as the writer, need to do the work of making the action come alive. Don't use tags to do that work for you.
5. Use tags only when needed. If there are only two characters in your scene, and they are going back and forth at a pretty good clip, there's no reason to use tags after each statement. If the reader can keep them straight, use tags only every once in a while to keep things moving easily.
Remember, tags are for the convenience of the reader. Make them as unobtrusive as possible and you will serve your readers a much livelier read.