I’m guessing dry it for a year or so?
with care and monitoring, you can dry it in a month
start roughing out the bow, but leave the bow the thickness of the handle for now and the width you need full length 1-1/4 thick by 2-1/2 or whatever
seal the ends and up the sides for a few inches from the ends
it will loose a lot of water the first few days, then loose weight slower. monitor daily for small checks forming and place in a cooler and or less dry place if checks start forming. (checks indicate the surface drying faster than the core) you can be more aggressive drying when more moisture has left
do you have a scale you can check the mass of the bow with and monitor the water loss?