Not all dogs like taking showers, but whether they prefer the spray of the shower head or a pre-filled bathtub, the temperature needs to be comfortable. Water that's too cold or too hot can be uncomfortable or even painful for your pooch, so make sure that both the water and the environment are just right for your dog. When you do, you may find that he doesn't mind being cleaned up as much as he used to.
Warming the Room
No matter what the water temperature is, if the room is cool, it's going to chill your dog—probably to an uncomfortable degree. Before you get the tub or shower ready, make sure that the room is warm and free of drafts. Close the window and any vents that may be blowing cool air, as your dog is going to be susceptible to losing body heat once his skin and fur is wet—even if the water is warm.
Warm, Not Hot
Whether your dog is taking a shower or a bath, the water should be lukewarm, not very hot or cold. Cold shower water is as uncomfortable for a dog as it is for you, and hot water can inadvertently burn his skin. Hot water also increases the risk of drying out your dog's skin too much, causing lasting discomfort and itching. When you wash a dog, you strip off moisturizing natural oils, which is why you shouldn't typically wash him more than once a month or so. Washing him with hot water only exacerbates the problem.
Bathing vs. Showering
All dogs are different, and that includes their varying preferences for showers or baths. While some dogs find it fun to be showered with clean water and will splash around, others become severely anxious when it comes time for grooming. Generally, dogs who are nervous about grooming prefer the relatively quiet, subdued bath to the comparably loud, high-energy shower. If you're trying to introduce showering to your dog, start small, such as by using an extendable showerhead to rinse him when you give him a bath.
Because dogs should be bathed or showered with warm water in a warm environment, giving your dog an outdoor shower from a garden hose generally isn't preferable. This type of water typically comes out unheated, and even on a warm day, the frigid water can be uncomfortable for your dog. If it's a breezy day, the combination of cold water and the wind can make your dog not just uncomfortable, but potentially dangerously cold, so resist the urge to simply take him out back and hose him down.