As far as I understand, and with each bdsm relationship being different from the next, the concept of punishment can fall between two extremes. One is where the submissive always tries their hardest to please and punishment is used as a last resort (after discussing every other option). The other is where the dominant takes pleasure in giving punishment at every opportunity (usually corporal but can be mental), and the submissive accepts it as part of their relationship.

As a guess if you are being asked to come up with your own punishment your relationship is probably closer to the first of those extremes, so I will concentrate my "words of wisdom" on that kind of punishment! Knowing very little about you I cannot possibly tell what would be "good" or "effective" punishment, so I am generalising.

As a basic and obvious point, such punishment should be designed to make you think before doing whatever you did again. Also each punishment should "fit the crime". Minor failure in etiquette (e.g. forgetting to say "Sir" if that's what the agreed form of address is) warrants a very light punishment - just enough to make you more likely to remember. At the other end of the scale major "transgressions" such as persistent refusal/forgetfulness/failure warrant much stricter punishment to make you think "I'll never do that again". That means there should be a number of different punishments you think of (or take ideas about).

My personal preference for punishment is always something that has some kind of beneficial side. And I've found one of the most effective forms is "withdrawal" of something which you do or like. So for example if you eat a lot of chocolate (and haven't got such a strong addiction that your health would suffer without it) going without it for a day or week is actually good for you. Caffeine is another good example of something that can be withheld.

Similarly stopping you "playing" (e.g. some online game) for a period would leave you more time to do other things. Preventing you leaving the house would mean you had more time for your family, etc.

Punishment exercise is good for you - a few laps around the block if you don't normally do that, for example. Also there is enforced relaxation where you have to sit still for an hour or more, which is good for practicing yoga and/or meditation which are excellent.

For one-off infractions having to write the reasons for your "misbehaviour" in some publicly accessible blog (obviously protecting your personal identity) is in my view a strong deterrent.

There are quite a number of other areas, but it is so dependant on the person and their own likes/dislikes etc. so I've just given you some examples here.

A friend suggested that as physical punishment being strapped on the bottom of the feet is effective, unless you really like pain.

Hope this helps
VV