In any relationship, one wants someone who is compatible, right? Well, the same goes for a D/s relationship, realizing that each D/s relationship is unique to the two involved. It is important that you not only know what your future Dom is all about, but that you know yourself really well. Does this mean that you are not willing to try new things to see if you like them? No, but it is important that you be firm with the things you absolutely know go against your grain as a human being. There are things that i would not judge others for doing that i would never consider doing, but that is just me knowing myself.
A good jumping off point, in my opinion, before looking for a Dom is to get to know your submissive self...what is acceptable and what is unacceptable. Some use a checklist, as i did, to find out all the things that are possible to see what you like, dislike, are curious about, never tried but want to, never tried and do not want to, etc. A checklist of possibilities could be made up yourself, but i found one that's got a lot to it, so i wanted to share that with you first:
After that is established, be prepared to follow a set of Dom's Rules. These are rules that should be customized around the checklist, so things you said NO, absolutely not to should not be something you agree to. You may be asked to recite His rules, so memorize them, if at all possible (or consequences may apply), but above all else, a sub needs to LIVE these rules, so make a solemn vow if you agree to abide by them and it will please your Dom to no end. On the other hand, break any of these rules and you will displease Him and have consequences...now on one hand, you are human and are going to make mistakes, but this will allow your Dom to...well...be a Dom and in part, it will please Him to punish you (you might just like being punished, so keep that in check wink).
Next, as mentioned in an earlier post, there are a lot of DomWannabees, so i wanted to include the link that talks about that - a great list for every one's eyes in my opinion:
Particularly in the beginning stages of a D/s relationship, a SAFE WORD is a must in my opinion. If the relationship evolves into something more hardcore, then changes can be made, in fact, changes can always be made when it is discovered that something agreed upon doesn't work for either of you, which means there should be a degree of flexibility.
It is important to mention that the pillars of a HEALTHY D/s relationship consists of Honesty, Respect, Obedience and Trust. Aside from that, it is always a good idea to make sure things are mutual, safe and sane!
Also, COMMUNICATION is extremely important. Your Dom cannot be the best Dom for His submissive if He is not aware of the sub's feelings, thoughts, fantasies, likes and dislikes, so you are going to have to be more open than you have ever been in any past relationship. You want romance, tell Him. If you want something from Him, tell Him...he makes the final decision, but don't refrain communicating (more = more). He needs to know as much about You as possible in order to be a good Dom to you.
This also means, NO GAMES - you are going to feel vulnerable at times, but it is best to be real. Even if one does not believe in 'Cause and Effect', it still exists and it is a good rule to live by in any case!
Lastly, it is important you both realize that while the Dom 'takes what He wants' - in actuality, the sub is giving herself freely, completely and that means the world to a Dom!