Every shopping trip may not encounter a bargain just for you. You may find some times you will only do window shopping. I don't buy just because it's a sale, my purchases are purpose driven. A clutter environment is not for me.
So often I may call a friend or family member when I see a bargain that may be of interest to them or a simple send them a picture of the item. There is no need of buying something if you can't use it.
Step back for a moment and visualize where the merchandise will fit in your home or if you can even wear it. If it's a thrifty find you just can't resist, buy it and donate to a local charity. There are so many others that can benefit from your thrifty finds.