Required effective seo suggestion.

Hello friends,
I have been working on one of the seo projects related online health insurance. I am doing all the activities like article submission, directory submission, social bookmarking, forum posting and blog commenting, but not getting the desired result as the keywords keep on jumping and some are still on the same position showing no improvements. Kindly suggest some different activities other than these one which will prove to be more effective and result oriented.
Thanks