First of all, always make sure that you use the correct past tense. If you don't, you're sure to sound like a big hillbilly.
Correct: I went to the store.
Incorrect: I had went to the store.
Correct: I had gone to the store.
Incorrect: I gone to the store.
You would be surprised at how many people make this disgusting grammar mistake.

Grammar lesson number two:
Don't end a sentance with a preposition.
Correct: I'm not sure where Travis is.
Incorrect: I'm not sure where Travis is at.
Do not commit this grammar mistake--it is one of the worst things you can do, and in our book, it is inexcusable.

Here's an etiquette tip that I shouldn't have to tell you about, but it seems to me that many people need to be reminded of it. When you are eating something do not talk. It's disgusting and nobody wants to see the food that's in your mouth.

More grammar and etiquette tips to come when I have more time!