Just message how many people you find attractive. That way should never limit yourself on purpose because you are in a negative mindset of,"well she would never reply to me" or "I might be sending out to many messages" you need to toss out a big ol net for online dating because a good amount will just ignore your messages.
One day set up a female account and put a random google image, and watch how many messages you get. it will be a lot and more then half just saying "fuck me" and then you will get the random message from the guy with zero confidence saying he has no chance in hell but took a chance.
Don't be that no confidence person. Don't be the bunny, be the bear. ooze confidence whenever you can, even if its online.