[Metatron]

Streets are always dynamic and your main subject - people - are always moving, changing their locations and expressions. It doesn't give you much time to think about, that's why, one good approach is to think less. Main purpose for street photography is that it should talk to viewer, tell him a story, make him ask questions about people in photos, that's why you can just shoot everything, that catches your eye, then after sorting you can find lots of pictures, that are telling more and more, as you watch them.
For starters, you might try just finding a good spot, where you can sit down, relax and take pictures of people passing by. After you get a grip on that, you are sure to move forward and try moving around, while taking pictures.
Mostly people perceive pictures with their subconscious mind, so you should trust it as well, while looking for subject around you. Yet never forget, to think out of boundaries.