First accept that sexual feelings and thoughts are a normal part of life and do not see them as "bad" or "excessive". See whether you are getting satisfaction in other areas such as work, hobbies etc. Having a fulfilling life workwise and some hobbies such as drawing, music, reading, sports etc and regular exercise also contribute to more life satisfaction thereby reducing sexual thoughts. If the sexual thoughts are intrusive or cause distress discuss with a doctor to rule out OCD.