Cut them in half lengthwise, check for 'critters' and clean for same, soak in mild saltwater for flavor (and to spook out any remaining 'critters'), fry in butter, and enjoy (supreme joy) especially as a side to steak.
Re: critters. Some morels from some locales don't seems to have the 'critter' issue (e.g. midwest U.S. hardwood forests) but others from, e.g. Pacific NW conifer forests, may have worm and/or slug larvae present inside the stems & crowns.