When I start to bake, I set my oven to 170 degrees. The oven vents ar the back of the stove by the back burners. That way a warm air flow is present and some heat from the oven rises.
I proof the yeast in 1/2 cup of warm water and a pinch of sugar. It if starts bubbling, it is good to go.
I use the water bath to warm my Rye sour for making Ryew bread every other week.
HTH
AC