If you do a tag search for "dating" or "coming out" you will find some other threads on this topic... generally speaking there seems to be a couple of more common camps of thought on this one...
The first being to be as open as possible right from the beginning in order to welcome and invite the type of partner into your life that would work for you... why go to the effort of dating and getting excited if they are not going to work out as far as the dynamic they would prefer? Telling them up front that you are poly and educating them means that you don't invest in someone that is not going to be willing to be with you in the way that is most natural to you... if they are interested it will be evident.
The second is the three dates theory... the idea being to let someone know after three dates that you are interested in being a partner with the person.. I guess this is to do with sex and commitment and that you won't know until having met the person once for a quick meet up, second for a proper date and third to seal the deal as to what their worth is to you and visa versa. Usually to have sex.
It tend to be a person who knows pretty much right away if the person is worth investing in... I said right on my dating profile that I was poly and tell everyone I meet that I am. At least I don't hide it. I am not ashamed or fearful any more and find that if I do this people who are interested or like minded gravitate towards me. Those who don't like the idea or are not like minded keep a happy distance.
I prefer not to spend time on people who are just too different, regardless of my attraction to them. Not that I am rude or don't hang out with them, just that I don't invest in them being more than an acquaintance. Hell, I've made some cool friends with people that are very different from me. But life is too short and my happiness, I have come to realize the hard way, is based on what I chose to do in life and who I spend time with.
There are lots of people out there to date, but if I spend my time on people that aren't suitable I miss the doors that open and miss opportunities to be with those that suit me more. Being open to all possibilities is how I met Mono and PN. I was honest from the get go with both of them. There were no secrets or info kept from either of them. Derby I met at a poly group... I totally advocate for seeking out groups of like minded people. That is the best bet if you ask me.
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