Find another method to relax. Nicotine is a relaxant, so you have to get an alternative to lessen your stress. A massage or yoga can be a really smart way of soothing, or you could try a warm shower, or listening to your favorite music. Whenever possible, try and steer clear of anything tense during the first days after you stop smoking.
Don't try to set the day to give up. Instead of trying to make a plan, quit today. This type of planning nearly never works and it will bring about disappointment. Start stopping immediately, as opposed to trying to make an imaginary timeline on your own.