Get a 5 gallon bucket with lid. Drill a bunch of 1.5 inch holes in the side and bottom. This will keep your net dry and have air flowing thru the bucket.
Take an extra 5 gallon bucket, fill with freshwater and throw some Dawn dishsoap in it. After using your net, when your done casting for the day, soak your net in the soapy water until you get back to the dock or home.
Rinse your net in clean fresh water at home or at the dock.
Take your net home, throw it out into a shady spot on the lawn. Let it dry before storing it in the bucket with the holes.
Every third or fourth use, soak in cheap fabric softner, overnight, then rinse and air dry the next day. If your net is new, do this right away, you'll be suprised how much better a soft net opens up!