How to warm up resin in warm water bath for large bottle

I first experimented with small bottles of resin. I placed the bottles in a bowl of water to warm them up and this helped avoid cloudiness. Now I have just ordered large bottles of resin and don’t know how to warm them up. I suppose I could pour into sealed smaller containers if I could predict the right expected size correctly? Or could I mix first and then pour into a sealed jar and put that in a warm water bath? (I assume not). ANy other advice would be great. Thanks.