Visit your local bike shop.
Some saddle manufacturers have a try-before-buy program for saddles.
Saddles are very personal and subjective so what may work for one person may not work for you. Everybody's sit bones are different.
Fizik and SelleItalia are a couple that have try-before-buy programs. There's a few others.
Specialized and Bontranger offer 30 day return policies for saddles that don't work for you and your local LBS may offer an internal saddle program that is not manufacturer specific.