Go for Off Page SEO techniques they will help you generate backlinks & that in turn will give you traffic.
The below are the things, you need to work with to stabilize the keyword rankings 1. Build quality relevant links, Very limited links on a regular basis. Don't go with creating profile links, Go with contextual link building. 2. Maintain the accounts you already built. For example: If you open a slideshare account, Make sure you submit a presentation every 15 days. 3. Schedule some posts in Twitter, LinkedIn and Facebook to get social exposure in a regular basis 4. Make sure you optimize the site regularly, Check with your Google webmaster tools for issues and fix them accordingly.
You have to continuously work on website. It is an on-going process to constantly update your site and its content. You need to build links over a period of time to maintain and improve your rankings.
Keyword mapping involves hierarchically classifying the keywords pertinent to your website by intent, relevance and significance, then segmenting them still further into groups and subgroups. The aim is to reach a point where each keyword you use can be closely associated with a single, specific page on your website, which should contain content that closely matches the keyword. If you haven’t performed this process, your page rankings are likely to be unstable and realistically, a restructure, with pages and content mapped to keywords, will be necessary to improve the situation.