A very mini list of things that I usually think of while I'm writing about life and tech, that have helped me to blog better!
My number one tip is that a blog post does not have to be polished and perfect (nothing is ever perfect!) before you post it. This blog post is a great example. It had been a draft for a long time, and I was hesitant to publish it. I waited and waited, just in case I could think of a few more tips. I mean, everyone would benefit from 15 tips rather than 10, right? Wrong. If I didn't publish, then nobody would benefit from even 1 tip. A draft post tends to remain a draft. Get your posts published. I want to hear your ideas!
You don't always have to write about the next big thing, or what everyone is currently talking about. Countless millions of websites use web technologies that are many years old. Write about whatever interests you and you will find an audience, trust me.
Blog about things that scratch your own itch. For example, you may have had trouble setting up a server, or found it hard to understand a JavaScript library. It can be anything. Posts that explain and describe how you solved a problem you experienced are really helpful to other developers.
If you are planning a complex or technical blog post and it seems intimidating, try breaking your plan into smaller steps. Limit the time you spend on each step–30 minutes, for example. Completing each step will help give your motivation a boost, and help you stop feeling lost in one huge task. You can use these regular motivational mini-boosts to keep going and help you write your post!
You may think of something you would like to write about, but do not know where to start, or have little idea how to structure the information. A good way to overcome this is to create headings, and place information under these headings. This can influence how you write and section your work and can help you get your awesome post out to the world faster.
As Anne Lamott, who wrote a book on how to write, says—get all your thoughts down in a "shitty first draft". Don't focus on editing grammar or spelling right at the beginning. Your draft will most likely change a lot as you are writing.
I don't use grammar or spellcheckers much myself but there are definitely a number of tools that can help!
Don't blog for attention or money! This will most likely make your motivation for blogging hit a roadblock, and fast. Blog for fun, let your creativity flow, and connect with other people. That's all it should be about. Other rewards are just side effects.
Paweł Grzybek 
TheGuvnor 
Andrea Contino