How can I improve my writing?

Without knowing many details, the only thing that pops into my head is to maybe try tackling a different genre or style than you are accustomed to and try to flex some different muscles.

disclaimer: I'm not a 'writer' & know that I cannot become one ;-))

Firstly, I agree with the 1st answer about trying to take up different genres. However, I'd like to add, that you can try to challenge yourself towards your specific goal by writing the Same 'story' in different ways ! This will be an exercise in creativity, divergent thinking And might indicate where your forte really lies, or what you enjoy most.

You mention that your writing "hasn't improved". Try to figure where & what really needs improvement/changes. Is it how you frame the sentence, is it punch lines, is it use/choice of punctuation, etc. etc. Once you can point to a few of such specific areas, it will be easier to tackle & work on them towards improvement. A generalized feeling will help neither identification nor practice.

You can also give some sample of your writing to your English teacher [or any other 'writer'] for an objective opinion, critical feedback & advice. Sometimes we are more critical of our work than others - they may like it, with a few wise caveats if at all.

Next, are you comparing your writing skills to any particular author-style or are you simply not happy per se? You are smart enough to realize that you need to evolve your own unique style or blend without trying to ape any other.

However, you will obviously do well to read as much as possible - good works from which you can gleam some ideas & inspiration. Try to deconstruct Why you like a particular style/author/para/chapter/book.... You might get part of your answer there.

Also try to read how-to-write books, blogs, etc. Some of these are truly informative & helpful.

Lastly, sometimes one simply needs to be "inspired" or "in the mood" to get things rolling. If we are at that stage/in that mood, we can do some of our best work - be it writing, painting, ideating, ...You might even think up a specific topic & try to write out an essay or short story. Write whenever an idea hits you. Develop it over more sittings & drafts. All writers go through several drafts, re-writings, editings, 'polishings'.... before anything is published :-)

Wishing you all the very best :-)

The more you practice, the better you get. The only way to improve your writing is to write.