I think the Both On Page and Off page Techniques are Effective techniques. Because for higher Ranking you need Quality Back links and for Higher SERPs you need Quality Content…
Do on-page optimization and then go for off-page optimization. Latest google algorithms have changed, checking website title and desc and then keywords before indexing in SERP’s. Use original content in your site.
Backlinks on very high PR Do-follow sites with relevant content, that have very few outgoing links.
I would suggest all On-Page techniques like Keywords, Title , Content ,Keyword density and the most important is the <a href ="http://www.sitemapxml.net"sitemap as this will also increase your rankings .
Then you can carry out with Off page SEO…