There is no easy way.. you have to follow Google Webmaster Guidelines
You need to perform some SEO Activity On Page and Off Page
On Page activity which need to be done within the website
Off Page activity for link building purpose (Quality Link Building is important)
ON Page
Keyword Research
Bold, Italic effect to main keywords
Canonicalization (If Applicable)
Competition Analysis
CSS Validation
H Tags Optimization (Eg: H1, H2, H3)
HTML Code Clean Up & Optimization
Image Optimization
Hyperlink Optimization
Link Validation
Meta Description Tags Optimization
Meta Keywords Tags Optimization
Navigation & Design Optimization
PR Sculpting
Robots.txt Optimization
Text Modification Optimization
Title Tag Optimization
URL Rewrite
W3C Validation
Broken Links Checking
OFF Page
Google, Yahoo & Bing Site Map Creation
Directory Submissions
One way link
Local Search Engine Optimization
Installing Usability Tools on Website
Article Submission
Blog Comment on Relevant Blogs
Blog Designing for the website
Classified submission
Creating Promotional pages on hubpages, squidoo, etc
Face Book Twitter Marketing
Press Release
Social Bookmarking
Video Submission
Article Writing
To check your site performance you have to use Google Webmaster Tools account setup & monitoring