If you take the shower while dreaming, then such dream indicates your desire to be clean with your thoughts, emotions and environment. Sometimes people who are feeling guilty taking a shower in their dream, because they wish to wash the guilt away. The shower could also represent the new phase of your life. Sometimes the subconscious mind is sending a message to look after you better, than you did until now. You need to let go your past and move on.
Read more about dreaming of Shower in other dream meanings interpretations.