Not everyone's the life of the party. Just try not to be the death of it. Here are four things that can make you seem boring...
1. Never having an opinion or taking a stance. Having a strong point of view usually makes you more interesting to be around. If all you do is regurgitate what other people say...or avoid taking a stance on anything...you'll start to come across as boring.
2. Having no sense of humor. When you have a lot of "cognitive flexibility," it means you can bounce from topic to topic and see things from different perspectives. And people who get good at it tend to have an easier time finding the humor in things.
3. Doing the same thing all the time. There's comfort in familiarity. But if you never step out of your routine, you become predictable. And people who are too predictable aren't very exciting to hang out with.
4. Having unbalanced conversations. Meaning you talk too much, or don't talk enough. Either one can make you seem boring. So try to find a balance where you contribute to the conversation, but don't dominate it.