Looking back through my old blogs (some are over 6 years old) has made me cringe if I am to be completely honest. The grammar was perfectly fine, of course, but I feel like the content was not written as neatly as it could have been. So, I will share some tips that will hopefully improve your writing and make it so you don't cringe as well at your 6 year old works.
1) Get to the damn point
I think one of the flaws with my old blogs was I spent too much time trying to bulk up my paragraphs believing that quantity would beat quality. This ended up making certain "troll blogs" lose their humour after a while.
A good way to avoid this is reread sentences and identify words that don't change the meaning. Take a look at the title of this paragraph for example, I could remove the word "damn" and it wouldn't change the message I was trying to convey. Adverbs are usually words you can remove from sentences.
2) Avoid "over description"
Your English teacher might have taught you to include details in your descriptions however I feel, as a reader, that too much information is boring. The way I've seen modern authors add detail into the world you're trying to build is by showing rather than telling. For instance, let's say Harry Potter. We first learn he's a wizard from a character called "Hagrid". We don't know much else about wizards but we aren't spoon-fed information either. Instead J K Rowling shows aspects of the wizarding with his shopping trip in Diagon Alley. The best part about her world building is the introduction of Voldemort. We are not told he's an evil wizard, we are shown that people are afraid to even mention his name.
3) Don't complicate stuff
If you try to get too creative with your stories, you might end up falling into dead ends you can't write your way out of. If the writer can't understand their own story, how would the reader have any chance? Creating a set of rules for your world is beneficial since it creates a sense of realism, but too many rules might leave your story with plot holes. Therefore I would recommend trying to establish a simple set of constraints for your world that could be exploited in a wide variety of ways.
As an example, imagine the movie "Back to the Future". We know that time travel is possible if you can move the time machine faster than 88 mph and provide enough energy. We also know there is some more advanced technology driving the machine. However, the exact details of the technology aren't shown which gives the world some simple rules that lead the characters into various problems.
4) Poetry tips
Poetry is interesting because there are various forms and therefore I can not give you a set guideline on improving every single form but I can try to explain the mistakes I think I made with my poetry.
First of all, in some of them I tried too hard to force rhymes to work which lead to using words that don't really make sense. Remember, you do not necessarily need to use full rhymes either, you can use a concept called a "half rhyme". For instance, the word 'orange' is very difficult to find a rhyme for but you can also use words such as "fringe" or "cringe" that partially rhyme. Using half rhymes can make your poems less restricted than they need to be. If you are a beginner, my advice is to try less strict forms of poetry so you don't have to constrain yourself.
I also failed to tell a story in some poetry. I think that poetry is not about trying to show off skills in wordplay, the message of the poem should be the most important. The best place to start with poetry is the title since this will dictate the theme you are following.
Make sure the world play you are using also makes sense with the given theme you've chosen. For example, you might have thought of an interesting metaphor that you wanted to use in a poem but that metaphor is only 1 line in your entire poem. Every line must count in a well written poem.
The best way to write good word play is trying to imagine visually how you want the reader to see the message unfold as they read the poem. Also, the length of the lines is just as important as the words themselves since the shape dictates how the poem will be read. Sometimes, you can deliberately make a poem hard to read (by using a lot of line breaks) to create a sense of confusion in the narration. Or employ a sequence of short lines to increase the pace of the reading.
I hope these tips helped and that you won't cringe at your old work in years to come.