This question has been asked multiple times on HP, it could have been Googled for no less than 1500 results, so by you asking it gives me the feeling that you are not one for research and or doing a manual search on the topic was too challenging of a task to complete.
I don't mean to be a jerk, but these hints already let me know you will be an underdog in making more than $20 per month with Hubpages.
Let me say this, making money on Hubpages is very easy and very simple. Here are the 4 easy to follow rules:
1. Write Quality Content, Often.
2. Have Discipline & Participate in the Community.
3. Write About Topics That You Know About and People Want To Know About.
4. Hubpages Money Machine Extends Beyond Hubpages.