Even though the actual definition of chivalry dates back to medieval times, you don't have to be a knight to demonstrate some courtesy toward the girl you like. Ask almost any girl, and she'll tell you that a guy who opens doors for her and offers to carry her books will win her heart every time. Most girls also appreciate a guy who offers to pay for the first date; it's polite, and it shows that you have a genuine interest in going out with her as well. Always walk to the front door to meet your date, and when the night is over, walk her back to the front door to say goodnight. You may not get a kiss every time, but we can promise you that your chivalrous actions will be met with a big smile.
Chivalry goes beyond simple courteous gestures. Be loyal to the girl you like, and never cheat on her with another girl. If you're a trustworthy person, your relationship will be healthy and positive, and both of you will enjoy being a part of each other's lives. Chivalry is also about following through on promises. If you tell a girl you're going to call her, remember to do so. If something comes up and prevents you from getting in touch with her, send her a text message or an e-mail explaining that you'll call her a little later than expected. Above all, treat her respectfully, whether you're alone, with friends or with her family. Making a good impression on her family is a surefire way to make her smile.