Well there are so many different things bloggers are doing right now but the main thing which every blogger do and have to is:
Write blog posts (articles) on their selected topics on daily basis.
As when we say Blog, it sounds like the fresh information.
So that we have to update blogs many times a month or on daily basis and there are some examples like TechCrunch and more blogs updating over 400 times a day with new articles every day and they are earning money in big numbers.
If you need more help, I am here