Your necklace has been freshly strung, and may appear tightly bunched at first. This is normal and allows for the beads to loosen as you wear the piece. The rudraksha seeds can get wet, but generally, prefer to be worn on dry skin and removed at night. It is not advised to let other seeds get wet. All seeds benefit from being next to your skin and picking up the natural oils from your skin. The seeds will gradually darken as they interact with your skin and the necklace will become very pliable. If you find that you would like to make any of the rudraksha necklaces a bit looser or longer, wet the necklace and then very gently stretch it, lengthening the silk. Be cautious in doing this to not pull strongly or for too long.
You can wipe clean with a soft, dry cloth and oil the seeds every once in a while using a small amount of gentle oil such as almond, sesame or coconut to preserve them.