Consult the temperature recommendations on the yeast package. Cool the wort to your target temperature. If youve harvested yeast from a previous batch or a bottle and dont have the original manufacturers temperature recommendation for your yeast, shoot for 60 to 72 degrees Fahrenheit for ales and 46 to 55 degrees Fahrenheit for lagers.
Make sure your keep the lid on your sauce pan except when checking the temperature to keep out contaminants. Also make sure your thermometer is sanitized before putting it in your wort, see the next step.