Summarize the following:
This really should go without saying. Unfortunately, largely in part due to Keanu Reeves, it doesn't. As an actor, you have to portray certain emotions and make sure that the audience can see what you’re feeling, whether you’re on stage or on camera. Use your own emotions to tune into your character's -- right now, they're one in the same.  Find an emotion within yourself that matches how your character would feel. Did her mom just die? Okay, so thankfully your mom isn't dead, but you remember how it felt when Poodle, your pet goldfish died and that sucked. You cried for days. Channel that. The audience has no idea what's your trigger, they just know that you're devastated and it probably has something to do with the plotline they're entranced it (if only they knew...). Manipulate the tone of your voice. If your character is upset, you might want your voice to sound harsher and less controlled. If your character is excited or nervous, make your voice go higher. Use gestures and body language to convey emotions. Don’t just stand there with your hands at your sides. If your character is angry, wave your hands and stomp your feet. If the character is sad, hunch your shoulders and hang your head. Be logical. Never, ever, ever, ever, ever give away that you've messed up. Never, ever, ever, ever, ever. Was that enough "ever" to get the point across? Whether it's in your voice or on your voice, don't let the audience know. If you don't let them know, guess what? They won't.  If you're dancing or moving, don't let your face drop. Confidence is fooling beyond belief. Stay smiling. Smile because you're the only one who knows. If you've flubbed a line, run with it. The only people who have the script memorized are onstage. Cycle back to where you need to go. If the other actor(s) is/are as professional as you are, there will be no problem. From the moment you step on stage, you are not dealing with romantic issues, money problems, or a general fit of fatigue. All that stuff is left offstage. You are only in the moment that is creating itself before you. If you're going through something during the run of a show, this needs to be an outlet. Theatre should destress you, not add to your plate. Take this moment to be someone else and check your problems (and attitude) at the door. You can pick it up in a few hours if you'd really like. Stop what you're thinking and start listening actively and being present. The audience will know if you're not. If you forget everything else, just remember that you have to be your character and not slip up and become your normal self. Theatre kids can often be pranksters -- resist the urge to laugh at the pair of Juan's boxers sitting on the bar you now have to use as a rag and be the best barman this side of the Mississippi. If there is a stage mishap or something doesn’t happen as planned, just stay in character and react the way your character would. Bell didn't go off? Find a way to work around that. Sometimes, worrying about messing up or other people’s reactions can ruin your state of mind. Often if you're having fun, the audience will be able to tell and have fun with you.  Take criticism with a grain of salt. If your director is telling you to do something differently, don’t take it as a personal insult. Instead, see it as a chance to improve your acting. Your acting improves and is more natural when you are having fun instead of stressing out. By being positive and relieving tension and stress, you’ll be able to slip into your character more easily. Practice relaxation exercises, get into character and stop worrying about how others will perceive you. You don't do this because it's anxiety-provoking! You do it because it feels awesome. Look in the mirror and say, “I am no longer myself. I am now [insert character name].” You are not yourself anymore, so you don’t have to worry about what people think about you. Remember that when you do something, audience members aren’t seeing you. They’re seeing your character. Be aware of when it’s your time to go on stage or enter a scene. You'll have half a dozen people on your case (besides the voices in your head) if you miss your cue. When it’s almost your turn, you should be waiting in the wings (or off-camera), getting yourself in character with your props ready.  Go to the bathroom before the performance starts. You don’t want to miss your cue because you were off using the restroom having a nervous pee or grabbing something to eat. Listen carefully for your cue. Even if you think you know around what time you’re supposed to go on, be aware and listen carefully to the scene that’s happening. Don’t get distracted or talk to other people. If there is an emergency and you absolutely have to go to the restroom or run to your car, let someone know even if you think you’ll be back in time for your scene. HAHA. Did you catch that? That was a joke. Funny, huh? Okay, okay, emergencies do exist. But unless someone died or your insides are about to explode, you make that cue. You'll probably not have to tell anyone as you rocket to the nearest receptacle, heaving your guts out. They'll most likely notice. When you’re in a play or on camera, you want to know where you should be spatially. To be put tersely, "find the light." Stay in it. It's there to illuminate you.  When you speak, turn slightly towards the audience. This is called "quartering." You want the audience to be able to see you and hear your voice while making it believable that you're having a conversation. If your director tells you you're closed, moved 90º (a quarter of a circle) outward. If you’re filming something, don’t look directly at the camera unless you're on an episode of the Office and the director tells you that you should. Instead, speak to the other actors and interact with the surroundings as your character would.

Summary:
Emote. Roll with the punches. Get in the moment. Don't break character. Keep a positive attitude. Release your inhibitions. Know when it’s your turn. Be aware of your position and surroundings.