Respectful. Dear, Lord, there are some people who assume being Dominant gives one an excuse to be an asshole. A good Dominant will never demand the obedience of a submissive they've just met. A submissive does not have to obey everyone. Respect, like submission, is earned, and a good Dominant will understand that. (Rule of thumb for Dominants: Approach a submissive as you would any man or woman you would approach in real life. Would you call someone you've just met a slut and demand for them to suck on your cock and address you as Master or Mistress? Thought not. Have some class.)
Patience. You're new to the lifestyle. You don't want to rush into things. (Dear, God, pleasepleasepleasedon'trushintothings.) So a person who understands and respects your pace is worth keeping around. I had once agreed to meet a Dominant over some coffee under the condition that there was to be no play the first time around. No more than ten minutes in, he urges me to come back to his place. I promptly thanked him for the coffee and left. The thirsty asshat. I said no play.
Experience and willingness to learn. Sad, but true. Not to disparage Dominants who are new to the lifestyle or anything, but experience is important. An experienced Dominant will use and honor the use of a safe word. An experienced Dominant will know how to correctly tie someone up. An experienced Dominant will know how to properly handle a flogger. An experienced Dominant will do his or her best to understand you as a submissive and will do everything in their power to ensure that all play activities and you are kept safe. Good Dominants will at least go out of their way to learn from or get advice from more experienced Dominants.
Humility. If he or she is 20 and calls themselves "Master" or "Mistress" and brags about having "trained" lots of submissives, a small red flag should go up.
Ability to listen. It pisses me off to no end how many Dominants can't listen or follow directions. I don't see D/s as a pro-de-quo relationship, but if a Dominant doesn't have enough respect for me to adhere to a simple request, especially when we are getting to know one another, I'm out. On FetLife, I ask that a friendly, introductory message be accompanied with a friend request. Countless Dominants have ignored that one, simple rule, and countless friend requests have gone to the trash bin. He or she should be attentive and be good listeners.
Honest and Communicative. Communication is paramount in a D/s bond. The Dominant should be comfortable voicing his or her opinions, needs, wants, concerns, and inquiries. Open communication is vital to satisfying both parties.
Compatibility. He or she's a sadist, but you don't have masochistic yearnings. They're into poly, but you're not into sharing. You want something more casual, but they want a permanent 24/7 Master/slave relationship. Compatibility is more than just kinks.
Fun. BDSM should be fun. Play should be fun. Your Dominant should be fun.
The list could go on and on, and apologies if my answer is a bit brief and vague, but honestly, trust your gut. Ask for someone else's two cents-this is just my input. Really, if you're a submissive on FetLife, the Dominants will come to you. You won't need to find someone. You'll just have the responsibility to weed out the fakes and pick the ones you find worthy to associate yourself with and possibly get to know better. Just because you're new and submissive doesn't mean you have to cut yourself short when finding a partner. Good luck and stay safe