(1) Use the Google Keyword Tool (which is free) to learn about which keywords are popular and have a low number of competitors.
(2) For now, focus on writing content rich hubpages based around these keywords. Include the keywords in your title and several times throughout your hubpages.
(3) You can build websites, or niche websites, around particular keyword phrases. Add Google Adsense to your sites to earn revenue. Include your links to your sites within your hubpages to get more traffic.
Really, the best thing you can do is research your keywords well and write as much as you can.