In general

• Politeness will get you a long way in the scene. Treat other people as you'd like to be treated.
• Honesty is highly valued in the lifestyle. Lying, whether about one's experience level, marital status, risk factors, or anything else is frowned upon, and will usually be found out.
• Touching (even casually) other people or their possessions (including collars, cuffs, and apparel) without permission is unacceptable. Most people enjoy playing show-and-tell, but always get their permission beforehand.
• Following someone around ("puppy dogging") is likely to creep him or her out, and make them want to avoid you instead of getting to know you.
• No Dominant may demand anything of another person, unless the other person has consented to engage in play or a relationship. No submissive is under any obligation to serve or obey anyone whom they don't choose to obey or serve.
• There are usually Dungeon Monitors [DM's], hosts, or people in charge at most organized BDSM settings. They are there to enforce the rules, but are not psychic; if you are victimized by someone, let those in authority know. They cannot do anything for you without knowing that something is wrong, and concerns reported after-the-fact become difficult to validate or enforce.

Play

• Do not distract or disturb the players.
• Never walk between a dominant and a submissive in a scene.
• Do not disrupt the scene, or invade the player's space.
• You may watch if invited, or if the play is in an open area.
• Always watch from a distance.
  
• Never invite yourself to join the scene: If you are wanted, you will be asked.
• Do not sit on play equipment while watching play -- you may be preventing others from playing.

Navigation in the Dungeon

• When a Dom[me] begins a scene, he/she will check for necessary safe clearances to use whatever toy he/she is planning to use (whip / flogger / singletail / canes / etc.). Once play has begun, his/her attention is properly directed toward the sub he/she is playing with, not people outside the scene. Therefore, if you walk into the space behind a Dom[me] and get hit with a toy on the backstroke, apologize quietly and assume that it was your fault for not paying attention -- not the Dom[me]'s for failing to notice you behind him or her.
  

Subspace, Sub Drop, and Aftercare

• Subspace is the BDSM term for the altered state of consciousness that bottoms / submissives go into during a scene or play.  
• Subspace is one or more of the following:
  

1. A profound natural form of "high," caused by the massive rush of endorphins and other naturally-occurring opiates released by the body in response to excitement or physical impact;
   
2. A state of very intense concentration similar to when one is completely and totally absorbed in a book, movie or game;
   
3. A feeling of intense mental focus on the exact moment of now (similar to the mental state sought by people who practice self-harm cutting in order to feel "alive" or "real");
   
4. An hypnotic trance state, induced or self-induced by the Dom/sub scene play;
5. The completely blissed-out feeling resulting from having just more orgasms in an hour than some women have had in their entire lives.

• Attaining subspace is a large part of why subs desire to play in BDSM scenes.   
  
• Remember a time when you personally were utterly, completely, and totally absorbed in a book, movie, or activity to the point that it WAS your entire world, and that world was utterly wonderful. Now, remember a time like that when someone suddenly and rudely yanked you out of that state, and how you felt toward that person in the moment. Multiply that by three, and you'll understand what the sub (and possibly the Dom[me]) thinks of you for starting a conversation with your friend next to a scene.  
  
• Sub-Drop is the BDSM term for the feelings of lost-ness, depression, or alone-ness, that can be experienced by many subs some time between 1 and 48 hours after a scene. It is analogous to the low which follows a drug-induced high.
  
• Aftercare is the BDSM term for negotiated care by the Dom after the scene, in order to avoid sub-drop.
  
• Aftercare is very important, and it is an expected part of most play scenes.
• Aftercare can make the difference between a wonderful experience followed by a horrible experience, and a wonderful experience that mellows out into happiness that lasts for many days.
• Generally speaking, the more intense the scene, the more likely the sub will need aftercare.
• As a sub, one should never be afraid to negotiate aftercare as part of a scene. If you are inexperienced, assume that you will require aftercare and negotiate it anyway -- if you later don't feel that you need it, it's a lot easier to dismiss it than it is to get it if you suddenly start feeling extremely depressed because the Dom wandered away after a scene.
• Aftercare generally consists primarily of wordless cuddling: Of making sure that the sub is warm, (covered by a blanket if appropriate to combat body-temperature-drop after playing), is supplied with water to drink to re-hydrate, is somewhere they can lie down or semi-recline, and is supplied with attentive but non-demanding constant physical contact.
• Aftercare is NOT the time to ask the sub how the scene went, or to try to have a conversation with them: A sub who is deep in subspace can feel completely at a loss to connect what they are feeling to any sort of words at all, and can need time just to process through the experience. Learning to simply hold, cuddle, and care for a sub after a scene can go very far toward being thought of as an excellent Dominant. 
  

Asking Dom[me]s Questions

• People in the kink world are generally quite friendly and approachable, and usually quite glad to talk about something that they were doing, a particular technique, or a toy they were playing with. So, generally speaking, if you have a question, don't be afraid to ask it.
• However, there are times when a question is intrusive: One is during a scene, and the other is during aftercare.
• If you have a question for a Dom[me] about something they did during play, be respectful of the fact that they may have a responsibility to provide aftercare to the sub they just played with.
  

Confidentiality

• Asking personal questions (one's real name, where they live or work, etc.) is usually considered rude until you've established a personal relationship with an individual.
• Confidentiality is very highly valued in the scene. Treat all personal information as confidential unless the individual in question tells you specifically otherwise. This includes e-mail addresses, scene names, home location, etc. It is also rude to ask others to break confidentiality for your benefit (for example, by asking for a third party's contact information).
• Attempting to track down someone outside of the BDSM arena without their prior knowledge and consent is generally bad form. If you absolutely must reach someone, rather than "hunting them down", have a mutual acquaintance pass a message along with your contact information.
• Don't take pictures or videos. EVER. In most dungeons, this will get your camera's/phone's memory card confiscated, and you ejected from the dungeon.
  

Interpersonal Expectations

• An individual's clothing or toy collection is not indicative of their BDSM interests or experience level. A casually-dressed person is not always a newbie, whereas the leather-clad goddess decked out in high-heeled boots and black PVC outfit might might just be trying to make an impression on her first visit.
• Expecting people who don't know you to call you 'Sir', 'Mistress' or another respectful title will make you look pompous. Titles and respect are both earned– let your behavior show others that you are worthy of your desired title.
• Submission/Dominance is not a competition. Pretentiously claiming to be the best submissive/Dominant, gloating over having the most or best toys, and other more subtle ranking tactics are unseemly.
• If a dominant requires that someone ask him/her before addressing his/her submissive, it is his/her responsibility to inform others of this rule. Strangers should be forgiven once (but not twice!)
• If you've prepared yourself by learning scene etiquette in an on-line chat rooms, do yourself a favor and forget everything. The fantasy of anonymous on-line role-play does not convert to actual, in-person behavior and etiquette.

Friends vs. Acquantainces

• You may notice people who are close to each other committing what look like flagrant etiquette violations. Most often these people are friends who don't feel offended by their close friends' jibes. Do not assume that because they can, you can.
• Not all submissives– in fact, very few– are instructed to be submissive to all dominants. Do not expect a submissive to be submissive to you simply because they are wearing a collar.
• Playful threats towards a submissive you're personal friends with may be considered cute and delightful. Playful threats towards a submissive you have just met will probably be considered an unsolicited advance or a general lack of etiquette.
• Likewise, tattling to a submissive's dominant about his/her misbehavior is usually considered cute and harmless among friends. Tattling to a submissive's dominant when you don't know either of them will make you look whiny.