Before we jump into the nitty-gritty, here are some basic rules of thumb to keep in mind. First, always use the complete, formal name of your invited guest. Your Uncle Steve? Formally, he’s Mr. Steven Lewis Nelson. Use a guest’s full middle name when you know it; if you don’t know it, simply omit it. Never use initials—in fact, don’t use any abbreviations at all. That means no ampersand, and no shorthand versions of “Avenue,” “Road,” “Street,” and “Highway.” This also applies to the State name—write out “Alabama,” don’t write “AL.” One last thing: for guests bringing guests, the “and guest” is kept lowercase.