Every person is unique and different, but mostly People feel a deep and very calm feeling, same as just before falling asleep at night or before waking in the morning.
People who are hypnotized feel deeply relaxed, sleepy, and pleasant heavy feeling in their entire. They feel their body is deeply relaxed, limbs heavy and their mind calm and serene. Mostly remember only some part of the things that hypnotherapist is said, although their subconscious mind has been alert the whole time, and open to the suggestions.
Feeling more relaxed afterwards and more positive towards their issues & challenges.
Almost most people remember everything or parts of the session, and it depends on how deep a person is in hypnosis. Even if the person don't remember all, but positive suggestion which have been given in the session will resurface when the person is in conscious state.