One of the most fundamental and essential aspects of SEO is the use of proper coding.
Page titles should accurately reflect the target search keywords, and the meta description should be about 160 characters and act as an attention grabbing short description of the data in the web page. One of the faults of this free hosted blogger platform is the inability to modify all of the meta data - each page should have unique meta data content.
Images should use alt text - this will help the picture show up on image searches. Title attributes could be helpful for your users, but it is not as essential from a pure SEO standpoint.
Any broken links or buggy code could hurt the rankings for the website. Inactive URLs should be re-directed to relevant pages.
These are the basic things to watch out for in the actual source code of a website you're trying to optimize for SERPs. It is much easier to get it right the first time before the page is published then it is to go back afterward and find problems.
