Here are three tips on "prep work" you can do prior to a first date:
1. In many ways, a first date is similar to an interview. Accordingly, you can prepare a few questions that you would like to ask your date to keep the conversation flowing. Steer clear of religion and politics, but feel free to dive into family, work, travel, hobbies, etc. However, be sure that your date doesn't turn into an actual interview; give him some time to ask you questions too, and let the conversation flow freely from each question.
2. Everyone has great stories about their lives, but not everyone is good at telling them. Pick a few anecdotes that are fun and lighthearted, and rehearse them prior to your date (orally, or in your head). Travel stories are always interesting to hear (like that time you rode a Vespa in the South of France, or went to New Orleans for Mardi Gras), as well as anything that is funny or unique that has happened to you. And definitely be weary of stories that might put you in a bad light.
3. The day of your date, make sure that you read a newspaper, or at the very least, glance through some news headlines online. If something really important or interesting has happened that day or week, you do not want to draw a blank if your date brings it up in conversation. Furthermore, it will allow you to show off a knowledge of current events. You can lead with, "Did you hear that..."
If you're still nervous about blanking out, you can take some notes on your smartphone to serve as your back-up. Also, if there's an awkward lull in conversation, you can always go with a compliment. People love to be complimented.
Who knows, with a little "prep work", you may find that you can even enjoy yourself on a first date!