The Sages prohibited bathing one’s entire body in hot water on Shabbat. There are also certain limitations with regard to bathing in cold water on Shabbat.

Even if water is heated before Shabbat, washing one’s entire body on Shabbat in hot water is prohibited, so that it will not lead to people heating water on Shabbat for the purpose of bathing.

Water that is heated on Shabbat in a prohibited manner may not be put to any use. Even if the water was heated in a permitted manner, e.g., for a sick person, a healthy individual may not use it. If the water warmed up without someone performing any action in order to heat it, such as water in a solar heater, it is permitted to wash individual parts of the body with it, as long as one does not wash the majority of one’s body.

With regard to showering in cold water, there is a difference between Ashkenazic and Sephardic practice: Sephardim permit one to take a cold shower on Shabbat and even wash his entire body. By contrast, although Ashkenazim permit the washing of all parts of one’s body on Shabbat in cold water sequentially, they do not allow one to wash his entire body at one time.

On Shabbat it is permitted to use only liquid soap, not solid soap.

Tooth brushing raises various halakhic concerns: spreading an ointment, which is prohibited on Shabbat; squeezing water from the bristles of the toothbrush; pulling bristles out of the toothbrush; and causing bleeding in the gums. For this reason, it is recommended to use mouthwash rather than toothbrush and toothpaste. Those who wish to use a toothbrush should find a high-quality brush with soft bristles that do not absorb water.

Some halakhic authorities do permit brushing teeth on Shabbat even with a regular toothbrush and toothpaste, if neglecting to brush the teeth causes discomfort, and even if the discomfort is only due to unpleasant breath. But even according to this lenient opinion, if it is known for certain that the brushing will cause the gums to bleed, it is prohibited. By contrast, there are authorities who completely prohibit using a toothbrush and permit only the use of mouthwash.

The use of stick deodorant is prohibited on Shabbat, but spray or liquid roll-on deodorant is permitted.

One may also spray perfume directly on one’s body on Shabbat. It is prohibited to spray it on clothing, as this would violate the prohibition against creating a scented object on Shabbat. Furthermore, some authorities are more stringent and permit the use of a deodorant or perfume spray only in order to disperse an unpleasant odor, but not in order to create a pleasant aroma. This is because they maintain that the prohibition of creating a scented object on Shabbat applies to the human body as well.