There Are Four main things what seacrh engines cares while crawling your site
1. Domain Name
2. Post Page Titles
3. Meta Description
4. Post Title Tags
1. Domain Name
Selecting a domain name is the most important thing in SEO. For Example if you are having a site regarding blogger templates than your domain name must be revelant to it like www.classicalmusic.com or www.classicalmusic.blogspot.comso that when visitor searches for classicalmusic on search engine than your website will be shown first in Results page even though Your PageRank is 0.
2.Post Page Titles
This is the Title of Your Post url. By Default Blogger Blogs Shows your homepage title followed by Post title which looks weired to Visitors and search engines may consider it as a Duplicate contentFor Example : my homepage Title is Best Blogger Widgets Plugins and Tools and Suppose you are viewing this post whose title is Make Your Blogger Blog and Template 100% SEO Friendly than it will show like Best Blogger Widgets Plugins and Tools Make your Blogger Blog and Template 100% SEO Friendly
To change it so that Post Title Appears first Followed by Homepage Title visit This Link
3. Meta Description
Meta Description are the Tags that describes your blog to search engines it contains description of your blog as well as keywords regarding your blog content. Most of search engines use this data to rank your blog.To add META Description Tags To Your Blog Visit This Link
4.Post Title Tags
This is the Title of your Blog Post which you make while Publishing posts in Blogger.This is the most important part of your blog as it describes about your post content.Most of blogger templates uses <h3> tags for Post Title which is consider as a normal content of your blog by Search engines.Even Blogger Default Template Minimia uses <h3> tag which is not SEO Friendly. To make it more revelant to Search Engines and make it SEO Friendly follow the Following Steps..Login to Blogger
Go to Layout---> Edit Html
Check on Expand Widget Content and Search For This Lines of Code
check for lines
<b:if cond='data:post.title'>
<h3 class='post-title entry-title'>
<b:if cond='data:post.link'>
<a expr:href='data:post.link'><data:post.title/></a>
<b:else/>
<b:if cond='data:post.url'>
<a expr:href='data:post.url'><data:post.title/></a>
<b:else/>
<data:post.title/>
</b:if>
</b:if>
</h3>
</b:if>
replace them with
<b:if cond='data:post.title'>then save template
<h1 class='post-title entry-title'>
<b:if cond='data:post.link'>
<a expr:href='data:post.link'><data:post.title/></a>
<b:else/>
<b:if cond='data:post.url'>
<a expr:href='data:post.url'><data:post.title/></a>
<b:else/>
<data:post.title/>
</b:if>
</b:if>
</h1>
</b:if>