1 FIND YOUR PASSION!
One of the first things you should ask yourself is "Am I interested in this subject?" If you are intent on building an interesting blog, it can take a good length of time and you will have to have sufficient interest in the topic to keep writing about in the long term. If you don't have the interest or passion to believe that you can still be writing about it in 12 months time then perhaps you should think about looking for another idea? It has to be something you can sustain and something you can write about with passion. If you aren't passionate, it will show. There is a lot of money in the football niche, but as it's a topic I loathe with a passion, it probably wont be worth my getting a blog about it!
What are you passionate about? Write things down, do a bit of mindmapping, freewriting or whatever but just try and find what your interests are. This all starts with you!
2 IS IT POPULAR?
Is the topic one that others are interested in? It isn't enough to have a passion unfortunately, others need to share it with you or you just won't get the readership. Its fairly crucial that others want to read about the topic as well. You have to be aware that popularity changes over time, it ebbs and flows. Who would have wanted to read about something called an iphone a couple of years ago?
3 WHAT IS THE COMPETITION.IS THERE ANY?
The internet is an increasingly cluttered market. Statistics are showing a move away from traditional advertising techniques, such as tv and radio to the internet. There is a lot of big business out there, elbowing in! Avoid falling into the trap of following what everyone else is doing. If its popular, someone has got there first! That doesn't mean looking for markets that are unpopular, its a question of balance. If you go into a really popular market, look for a fresh angle on it. Always try and be a big fish in a small pond in the words of that old cliche.
It can be healthy to have competition. It shows that there is a market there. Too much competition can make your task an uphill battle, too little and you won't have any readership! However some of the most profitable niches are built around those topics that have little or no competition if its a topic that interests enough people. Have a look at what the competition isn't doing. Look for the gaps. Research and try and find a sub niche within a niche.
This goes back to your passion.Have you enough to keep writing and finding content? Is there enough in you? Do you know where to find other sources if you find yourself drying up? Content is king and in order to have a successful blog, you have to be prepared to write on what you know and research what you don't. Keep in touch with the world out there and subscribe to newsletters,forums and link to other blogs for your content. Keep an eye on the google world as well by looking at Google news amongst others. If you can write on "whats hot" you have a better chance of getting new readers and interesting the old ones!
5 CAN YOU MAKE MONEY?
This might not be your motivation in starting a blog. If it isn't then that's fine. Many bloggers are writing just for the passion of writing about what they love and have no interest in making any money from it but if you are thinking of starting a blog and monetizing it,you have to think about where it may make some money for you. If it is a motivation in starting a blog, consider whether it is a topic that has any earning potential. Will you be thinking of getting AdSense onto your blog,what affiliate programmes are there in the niche? What about looking at Amazon.com. There are a lot of ways of monetising your blog.
6 CHOOSE YOUR WEAPON
If you are really interested in starting to blog, get on and choose a topic. Don't spend months thinking about it, take action. Its unlikely that you will find the perfect answer. In reality there will be weaknesses in any approach, but if you don't get on with it make a decision and start blogging, you probably never will. Accept the inevitable, nothing is perfect. The only true answer is to get on with it, be aware of the weaknesses and work to avoid them or use them to your advantage if you can't. It is only by starting this process, that you can learn to "tweak" and learn to grow.