At a group ride, with friends, ask to sit on as many as you're interested in. That may rule a few out.

With the above info, take your bike to an lbs that will allow you to mount it in their trainer and try athose that made your short list. Most shops will allow this if you've committed to purchasing a saddle from them. When Mrs. Fred was in the market, three different shops offered, that if she purchased a woman's saddle from them, she would be free to exchange it for other saddles for the difference in price as long as she hadn't ridden it in the rain or damaged it. They were willing to accept clamp marks on the saddle as long as she was willing to accept the same from any saddles she tried and eventually purchased. Selle Italia and I believe Specialized both have "test saddle" programs that provide shops with one each of their saddles at reduced cost for the purpose of loaning them out for this very purpose.

Basically, narrow your choices down by eliminating the uncomfortable, then trial a few to find the best fit.