Where can I wash my dog?

Besides groomers, some cities now have self-serve wash station dog businesses (look online to see if there's one near you) which can help if you have difficulty lifting the dog into the bathtub or sink (ideally with a sprayer attachment that can be turned of between rinses. From what I've seen they also offer grooming services there if you end up needing it. Some veterinarians also offer complete bath/grooming services.

You can wash your dog with a lukewarm water and dog shampoo in a bathtub. Or you can take him to a groomer to get a bath.

I've washed my dog in the shower, as I take a shower. I obvious don't blast water in his face, I use a cup, I hold him in my arms to get him wet, and I have my husband dry him as soon as he is done (while I finish washing myself). If you have a particularly fearful dog, I would not recommend this.