Are you enjoying street photography but find that your photos aren't quite at the level you'd hope for? After four years of practicing the craft, I've learned some skills and lessons that you might find insightful. Let me first say that your creations are important regardless of the mastery level you are currently at. As long as you love what you're doing.
Street photography can be divided into multiple categories - documentary, aesthetic, witty and humorous, even street portraits, although not candid, are considered to be part of it. So there is no one right way to do it. I'll give some general advices that will work for whatever genre you're most drawn to.
Too much clutter. Not paying attention to little details.
Usually as beginners we tend to focus on the main plot of the scene and forget about details that could ruin it. For example, these could be objects sticking out behind the main subject, trash cans at the edge of the photo, crooked lamp posts, people cropped in half etc.
Having your photos clean adds to the visual appeal. It doesn't mean they can't be messy, but make sure you consciously choose what to include in the frame. And have the subject clearly defined.
I'll add here the importance of not over-editing the photos. It's best to stick to the classic look and slowly develop your style. Too much post-processing can be a sure way to ruin a photo.
Poor light conditions
When you first develop the courage to start taking photos of strangers, it might pull your focus strictly towards capturing an interesting person in the frame, while disregarding light conditions or backdrop. This leads to an incomplete photo because no person can make up a great photo if it's not in the right environment.
It's not a bad practice to look for a good light and nice background first, then hanging around the spot while a fitting character walks in and completes the scene. Make visual memory of how light moves around your city throughout the day so you always know where to head towards.
No clear subject. No storytelling.
I often encounter photos that are a snapshot of a street scene but what's missing is the clear main subject. The problem with these is that the viewer's eye wanders across the photo not knowing what to focus on. I'm not talking about the aesthetic/minimalistic scenes although it works for them too.
Examples are subjects that blend too much in the background, are too dark, perhaps there are multiple subjects in a scene that begs for one. If you purposefully include multiple subjects to tell a story, are they well balanced/placed across the frame? What is the subjects relation to the background? Just some questions to ask yourself when composing.
Not getting close enough
It's been repeated many times, and still true. The difference between a mediocre and excellent photo can simply be few steps you take closer to the subject. Look for everything that does not fit in the image, then exclude it by getting closer. Less is often more. The subject's expression and emotion is more emphasized. It adds dramatic tone to the photograph.
Below are exaggerated examples that work well. Getting close is a challenging task, especially for beginners, because of the fear of being caught and confronted. There are many ways to make yourself look friendly and unobtrusive which I'll write about at some point.
Not working the scene
In order to have a great composition, it's necessary to work around the scene and find the best point of view. It's very unlikely to stumble upon the perfect angle with the initial approach. But as beginners, we tend to walk too fast and let fear dictate the way we shoot.
Instead, take your time, don't shift your focus to new locations as soon as you take a single photograph of the current. Think about alternative ways in which you can tell the story. Some things might be better off excluded or added. Maybe a person in white or a lady with a red umbrella would be a better fit with the background. Who knows, maybe they are just around the corner.
I hope you find some of these ideas helpful. Remember that practice makes perfect, so go outside and have fun shooting.