A good slave should remember all rules set up by his or her owner. He or she will do their best to uphold those rules and keep within the agreed boundaries. Some subs like to push their owners, challenge their authority or be naughty; this only works if the dom/domme is compliant in such games. If not, the sub is breaking the golden rule by putting their own needs above their owner's.
*Expect nothing in return
If a dom/domme usually indulges a sub with a particular pleasure at the end of play, and one time chooses not to, this should be of no consequence to the sub. If the sub gets frustrated or annoyed, they're forgetting their sole purpose: to serve.
*Pay attention to detail
A good sub should be aware of how to please a dom/domme in every way possible. If you discover that your master or mistress has a weakness for chocolates, lavish them with the finest you can find. If they've always wanted to see you dressed as a cheerleader then turn up in the costume one day. While it's important that a sub sticks to rules and does exactly as his or her owner tells them, surprises like this show that the sub has been listening, is thinking of the dom/domme, and is trying to please.
*When in role, stay in role
Unless it's literally a life-or-death matter, no outside influences should be allowed to break the spell once both dom/domme and sub are in role. There's nothing worse than a phone ringing in the middle of play and a sub suddenly saying, "Oh crap, that's my sister calling me from Detroit. Do you mind if I take it? It might be important." A good sub may inwardly kick himself or herself (and be punished) for leaving it on but, knowing their place, will ignore it. A really good sub wouldn't even give it a moment's thought; he or she would be too lost in servitude.
*Take care of yourself
Remember, as a slave you're someone else's property and, as such, you should be well maintained. If your owner prefers a trimmer figure, longer hair, or wishes you didn't smoke, it's your duty to do your very best to fulfill these requirements. A good owner will want their slave to be fit, strong, and groomed. A mistress or master who encourages their slave to drink more, wash less, and grow a neck beard, however, isn't worthy of being served.
*Never complain or argue
Nothing will annoy a master or mistress more than a whiny slave, complaining, being demanding, or trying to tell their owner what to do. If, however, a sub is suffering in a way not conducive to play-their bound legs hurting, for example- he or she should always approach the issue in a tactful, apologetic manner. The slave should never tell their owner how to rectify the problem; that's the owner's role, not theirs. "Master, I'm sorry to bother you but I think my legs are getting pins and needles", is much better than, "You need to untie me; these restraints are hurting my legs".