There are many ways you can improve your street photography. But one of the easiest and most fun is to look at the images of master street photographers. Simply by studying their work you will learn about new techniques and get ideas that you can use in your own photography.
Looking at other peoples work can also provide you with the inspiration you need to get your own personal project off the ground. So if you are interested in starting your own project, or if you just want to learn some new techniques from the masters, then I highly recommend taking a look at some street photography books.