There are two types in SEO

1) On-page optimization
2) Off - page optimization

On-page optimization:

 On-page Activities:

 Title optimization
Description optimization
Competition Analysis
Content Optimization
Internal Linking
URL Structure Changes
Site-map creation and updating
Site loading time optimization
XML sitemap.robot.txt, canonicalization 
Meta tag optimization
Keywords Research
301 Redirection
Image Optimization
Unique content

Off-page Optimization:

                                        

Off-page Activities:

Directory Submission
Social Bookmarking
Blog posting
Blog Commenting
Forum Commenting

Posting Stories in relevant blog websites

Article submission

classified submission