But if one showers at a different time of day from the appointed shaving time (or skips showering altogether on a given day), getting a warm shave can have its challenges. For example, my home is a ranch style, with the water supply entering the house at one end, where the hot-water heater is located. My shaving area is at the other end of the house, and even in summer it can take a while for my shaving faucet to run with warm water. In the winter, even longer. It keeps going and going like the Energizer bunny -- only in a bad way.
I've found an easy, responsible way to solve this problem, to come in from the cold like a suspect British spy in the 1960s, while still being ecologically astute. I adapted the idea from the 19th-century, pre-indoor-plumbing practice of having a pitcher and bowl on hand, and not relying on the bathroom faucet (much).
I prep for my shave with (as usual) two or three splash-and-rubs on my beard using cool tap water drizzling out of the faucet. Then I shut that off and pour warm water from the carafe about a half-inch deep into a re-purposed Greek-yogurt container. Then I saturate a wash cloth with more water from the carafe. I then apply the warm, wet wash cloth to my beard. I end the pre-lathering process with pouring from the carafe a small amount of warm water into my palm, with which I dampen the clean, whispy dried lather on my shave brush from previous shaves.
I apply dry shave soap to my wet beard, dip the brush into the yogurt bowl containing warm water, and face lather -- re-dipping my brush into the warm water as needed.
I take my usual patch-and-anti-raking shave, without rinsing used lather from my razor until the shave is completed. After shaving, I pour the warm water remaining in the carafe into my hand and rinse remaining soap residue from my face and neck. Voila!
Do be a do-bee and don't be a don't-bee: consider being more ecologically responsible in all actions (and stop denying the problem, like some dumb-ass politician-elects, who assert that global warming and related climate changes are a hoax perpetrated by the Chinese -- idiotic, uninformed!). Recycle; drive smaller vehicles and drive as little as you can; use everything up and don't discard when things are still usable. Don't waste, period. Eat less animal protein (watch the movie, Cowspiracy, on Netflix if you don't understand the less-animal-protein thing).
Happy ecologically-aware shaving!