I write my posts, usually in one sitting. Whatever comes to my mind, goes into the post, and thus, at times, there are chances of broken sentences and thus resulting in meaningless paragraphs. Usually, when I sit composing a post, I try not to indulge in something which hinders my thought process. This results in minimizing most of those broken/half completed sentences. Once I complete my post, I quickly go through it in the word doc, where I create my post, so as to have an offline copy of my post, in the event of something going wrong. This means that I have a backup copy of almost all of my posts in my computer (almost because I realized and started doing a bit late in my blogging career. Once done with this, I go on selecting the pictures, watermarking them, uploading them and placing the pictures at a proper place in the blogpost, after adding the copied text content I compiled in word doc. This allows me some time off the written content. Microsoft Word's inbuilt spelling and grammar checking facilities further trim down the chances of incorrect spellings, grammaratical issues with the text content. Again when I finalize my post, proper with all the pictures, formatting, captions and alt tags of the pictures, I go through it in blogger's post composing screen and again before I hit the publish button, I preview the post, and go through it. Once I am sure that there are no more mistakes in the text, I publish it all. And doing this, a mail notification is sent to all the subscribers of the blog, including me. Again I read the live post on the blog. This lets me go through it in about the 5 minute gap between the post going live on my blog and it being published on my blog's feed, and on my blog's Facebook and twitter pages via that feed. Being published on the blog's feed is more important than being published on your blog. If it's on your blog, you can always change it, but if it's been published in your feed, you can't edit it and you'll have to live with it. So, I am proofreading my post - 4 times before I am completely satisfied that the right thing goes.
Even then there have been instances that I have found issues, both typographical and grammatical, in my posts. I correct it there and then. 
And this is usually true for my essays here as well. 