There are a lot of tricks and techniques used by good roleplayers and narrators, but fundamentally the ultimate secret for success is to be mindful of the moment. It's the ability to fully engage in what's happening during the game that is the mark of a good player. This doesn't mean you will be constantly talking, acting, whatever - in fact that is actually the mark of someone who is not fully engaged in the game. Roleplaying is a group activity. To be truly mindful and engaged means accepting and embracing that group dynamic. This is hard. Humans are naturally self-conscious, which puts our mental focus on our perceptions rather than the reality around us. Narrators have a tendency to dwell on the climax and conclusion of their adventures, not the present moment. Players have a tendency to be focused on their own wants and needs, leading them to become bored or distracted when the attention is elsewhere. With duets it's a lot easier to be focused; less players means less distractions, and this is one reason duets are more intensive and quicker paced. However, I do want to discuss how I view the right mindset for roleplaying in general. I think this is one case where the lessons of duets can be applied to groups.

Active Listening

Listen. Really listen. Listen to the narrator, listen to your fellow players, figure out what they're trying to do. Ask questions, interact, but all the time listen. Everyone's dropping cues during a roleplaying game and the best roleplayers know this, listen for the cues, and pounce on them. If the narrator is trying to conjure up a scary adventure, then pick up on and play into that, don't take a comedic track on the adventure - show some fear and hesitation! Being mindful of what's going on at the table really gives you a lot more to work with as either a player or a narrator. It's not just the narrator's job to make sure everyone is engaged and enjoying themselves, that's the responsibility of everyone at the table. Often the mark of a good group versus a more dysfunctional group is how much of the burden of the fun and success is on the narrator alone. It really is a team effort and once a group realizes that then things will fall into place. However, before you can get there you need to be listening.

Don't Waste Time

Time is precious. If what you are saying or doing really only affects or matters to your PC then make it quick. The more people at the table involved with what you are doing the more worthwhile and thus the more time can be spent on it. Sometimes you might be doing something that while it's all about your PC is very entertaining, then it's worthwhile, though remember that what is really entertaining to you because it involves your character, may not be as entertaining to everyone else. Also, remember the spotlight isn't suppose to rotate between players but stay focused on the group. The spotlight is best kept on as many characters as possible. Consider any movie or play, sure there maybe be scenes where one character is all alone on the stage but the best scenes are pretty much always when there are multiple characters involved. This is very true of roleplaying. There's only so much time in a session so every minute that involves everyone is the best use of time. Related to this is the need to keep the pacing moving, which means being decisive to keep things going forward.

As an aside, this is something that really marks the difference between duet and group adventures. The approach to each of them and how the 'spotlight' works is very different. With duets, you hone in on the sole PC. When you run groups you may often want to do the same there, so as to give each player in the group a duet experience. This can work but really I've learned that the better approach is to focus on giving the group a duet experience. That's kind of hard to explain but the essence of it is entailed in this article.

Don't Intrude

If your PC is out of the action, then accept it. Listen or take a break if you must but don't intrude unless appropriate. Sometimes a witty comment, encouragement, or an idea is appropriate even when your PC isn't there but generally don't get involved. Ideally, the other player will try to draw in everyone else but regardless sometimes players need the space to do what they want with their PC. In other words do onto others as you would have them do onto you.

Help Others

The best roleplayers know the truth: if you help others they will help you. The trick is understanding what it means to help others. The goal is for everyone to be engaged and involved with the game. You need to bring everyone into the fold. This might mean your PC talks with their PC or it could mean your PC insults their PC to create conflict; it can be complicated to figure out the right approach but interacting with others is key. If your PC is always away from the other PCs, sending secret notes to the GM, and pulling away from the group, then you aren't being helpful to the other players - you're really not giving them anything to work with. As I often do, here is the complete opposite advice under the same heading: don't help a player stuck in indecision unless asked. Some people need more time to process a situation and in these cases you need patience. Related to this is the fact that if another player comes up with a 'bad' plan then let it run to fruition, don't jump in to offer your 'better' plan. This is helping others in an important way. This probably sounds complicated. You can help by maybe helping, maybe setting up conflict, or maybe by doing nothing. Wow. This is why some people are better at roleplaying than others, because it does involve reading complex social cues but at least making an effort will yield results.

Give People Stuff to Work With

Your characters need flaws, passions, personality. However, you need to tailor them for other people to utilize. When you are considering aspects of your character's personality, ask yourself the following questions: Will this be useful to other players? Will this help me or others roleplay their character? Will this be too distracting? This last question is critical. It's a fine line between creating a character others can work with and a character who is an annoying distraction to the game. My advice is to keep characters tight in design. You can always add more depth down the road but really your paraplegic, racist, dark elf Jedi assassin is all about your ego and not something that'll work well with a group.

Additionally, have goals, ambitions, and dreams for your PC. Don't be passive! The best roleplayers have dynamic PCs who are engaged with the setting because they have things they want to accomplish. Other players also respond well to this for if as long as someone has goals then the group has goals, even if they're just tangentially connected.

Proper Etiquette

Obviously, be on time, don't be distracted by electronics during the game, don't be disruptive, clean up your mess, and be a good host or guest.

Be Organized

You need to know your character and what's going on in the campaign to be mindful of what's happening in an adventure. Take notes, update your notes, and pay attention. As a kindness to the group, you can use your notes to give cues (like reminding everyone of a name or event) to the other players and narrator.

Ask Questions

People in general don't ask enough questions. Asking someone questions about their character can help a shy person to feel involved and help someone who hasn't given things a lot of thought to flesh their character out. Asking the narrator questions about the campaign can help everyone visualize the setting more clearly. Don't pester, but do express interest in what the other players are thinking and doing. Related to this is the need to express your feelings. If you are bothered by something in the game or out then you need to express it. If someone says something that crosses a line, don't sit and stew - call them on it. Communication is a critical thing that is seriously lacking in most groups. Politeness can be deadly. I feel it is far more impolite to be silent if you have a problem then to express it. Life is to short to be silently and stoically miserable.

There you go a very scattered collection of points on how to be a mindful or engaged roleplayer.