How do I set it up to cook in liquid.
The easiest way is to use a heavy duty Ziploc bag. Put the meat and liquid in the bag and use the water displacement method to remove most of the air then seal the bag. Then proceed with your recipe. An alternate approach using a vacuum sealer is to place the liquid and meat in a bag and initiate the sealing before the liquid is pulled out. Water displacement is probably easier.
Water displacement is submerging your bag in the cooking vessel water allowing the air to escape. When you get to the top and almost all the air is out you zip it shut.