Writing original content is ofcourse the key. But if you want to be a success and/or make money, you need to research the areas first to see the demand and to make sure it is not in an oversaturated niche.
Try the following:
Choose a topic and break it down into sub topics
Use the google adwords keyword tool to ascertain keyword phrases
Choose one with less than 20,000 searches
Write a few hubpages using the keyword phrases while still ensuring they read well.
Ping your hubpages
Social bookmark your hubpages on at least 10 social bookmarking sites (eg digg).
Write comments on blogs and put your webaddress (when the field asks you to) as your hub post. This way if people click on your name they will be taken to the hub post.
Hope this helps.