The worst mistake you can make if you are writing a blog/article/book

Ask your friends to read it.

First, most of them will only do it out of obligation. For some folks you will have to hold a gun to their head or threaten to beat them with a rubber hose or make them stand in an ant bed or something.

Second, you are not as good as you think you are, so this puts your friends on the spot. If they even respond, they will have to lie and say it is great or something.

If you want to write an article for the paper, write it, send it in, and don't tell anybody.
If you run a blog, let people keep up with it on their own and never ask them to go read anything on it.
if you want to write a book, well, the odds of getting it published are about 100,000 to 1.

I read the above about 10 years ago in an article about non-writers trying to write. It was much longer (and much more entertaining) but this is the gist of it.