State the obvious
Just because you know something doesn't mean everybody else knows it. Don't be afraid to talk about things that seem obvious to you – there's a whole internet out there and quite a few people who won't know what you know. The added bonus of explaining something obvious is that you'll automatically be an authority on the subject. Believe. Know how to tie shoelaces? Someone doesn't. Know how to make toast? Someone doesn't. You get my drift. A 'How to...' post title always gets a lot of interest because a huge amount of internet traffic is people seeking information – particularly about things that are so obvious that they are afraid to ask their mum/wife/boss about in case they laugh.
Recognise your successes (and your failures)
Getting through your day is a success. Getting enough money together to pay the bills and feed the kids is a success. Getting this far into my blog-post is a success. Recognise these successes and use them as material. 'How to get through your day without killing your boss' is a post anybody would like to read – detail the mechanisms you use to avoid boss-homicide, no matter how trivial they seem. Readers will empathise with situations they recognise, no matter how trivial-seeming they are to you.
Write what you don't know
To produce regular blog-posts requires a lot of material. Eventually you'll come to a point where you feel like you've blogged about everything you know or have ever experienced (in fact, you haven't, but that's beside the point) – this is the time you have to start making shit up. If you've blogged about everything you know now it's time to blog about what you'd like to know. This is an opportunity to broaden your horizons. You've blogged about how to cook risotto, but you'd like to know how to cook a curry – learn how to cook the curry and then blog how to do it, or blog how you learned to cook it, or how you failed to learn how to cook it. All of these things are lessons that readers of your blog could learn from. Obviously you're going to have to do a little research for these kind of posts, but hell, you'll be learning about stuff you want to learn about as well as delivering interesting content.
Write the post you'd want to read
When stuck for ideas come up with a great-sounding post title and build up from there. 'How to fly to space with only a saucepan and a hairclip' is a title that's going to get hits. The challenge then is to come up with the content to support the title. Build five bullet points to support the title, then use these bullet points as sub-titles to support with content. You'll find that as you start writing ideas to support your headlines you may come up with better ones – don't be afraid to change them – the punchier or more interesting the better. Ok, flying to space in a saucepan is a tricky one, but I used this mechanism to produce this post and some of my more audacious (and popular) posts.
Just do it
I'm frequently surprised at what posts get a lot of interest – posts I dashed off shame-facedly go viral, while lovingly crafted sure-fire winners get ignored. Sometimes you've just got to take a chance with a post. Ones you think controversial may barely raise an eye-brow and others you think harmless may kick off a shit-storm. The lesson here is a bad post is better than no post at all – because you never know, that post you thought was hopeless may actually end up being the post that puts your blog on the map.