I've said it before so those of you who read here a lot already know what I might say. . . Decide for yourself what you want out of relationships before you are in one. If you don't know what your needs are, there is probably no way someone else will be able to figure them out for you.
In the poly world that is even more important since unlike monogamy, polyamory comes in assorted flavors, sizes, and varieties. Almost like going to a build your own sundae bar. If you don't know what you want before you get there you will end up with a bit of everything. Sometimes that is okay, sometimes you end up with a complete mess.
Now this is where I leave you hanging because there is no magic potion, recipe, or place that will help you figure out your needs. I think you need to be in touch with who you are to figure that out. Fortunately when the time came for me to figure out my needs in polyamory it was as simple as learning the language because I had already been living it, just not as polyamory.
This is where I make up for leaving you hanging. . .
I am a very good Secondary but I will never be a Primary. Despite that, most would define me as a Primary in relationships.
And once again you are thinking, "Is he smoking crack? I know he doesn't like or believe in relationship hierarchy, and not only is he using it here but he can only be a Secondary?"
Well, sorta. I am very comfortable being in the position of Secondary with a woman who is married or has a Primary. I can easily respect boundaries, limits, and needs of her other partners. That fits with my personality somewhat, I enjoy rules. (Yeah, I know, sick isn't it?).
But in my relationships I believe in equality. If someone new were to join my family I would consider them equal, on the same level, or whatever you want to call it as my existing partner of 3 years. I wouldn't give either preference over the other.
That seems to be where some people classify my relationships as Primary. Because not only do I consider my partners equal, I consider their importance in my life to be equal to that of (for lack of a better term) a true partner. I regard them as family, depending on them and supporting them as any family would do.
I believe that my knowing this, being able to see my needs, is what allows me to enjoy polyamory when I hear others talking about failed attempts, exploded or explosive relationships, and constant drama. Upon entering a relationship I usually am able quite quickly to realize whether my needs will be met, how well, and sometimes even how long. Knowing that fast allows me to adjust to realistic expectations and be less surprised if things don’t last.
My suggestion to you is to simply know what you want, and what you can give, in a relationship. If you know you can't be a fulltime partner, don't get involved with someone who wants a fulltime partner. Likewise if you want a fulltime partner, don't enter into a relationship with someone who can't commit the time you need. If you need more exclusivity, maybe dating someone who already has 2 or 3 partners isn't your wisest choice. At the same time remember that polyamory is as much about designing a relationship paradigm that satisfies your needs as it is having multiple partners. Find a design that fits you well and you will much more easily find partners that fit your design.