Most people still try quitting smoking cold turkey before they try other methods. If that's worked for you in the past, you might want to try it again, and focus on what you can do differently to stay quit this time.
If you decide to quit without quit-med support, you can expect that physical withdrawal symptoms may be more intense. For many people, the first 10 days are the most difficult, after which time your system becomes more adjusted to being nicotine free. Many people who relapse during that first couple of weeks do so because they give in to withdrawal symptoms.