First thing to do is to enable SEO URL’s from admin, System > Settings > Edit > Server > Use SEO URL’s.
Rename the htaccess.txt to .htaccess using your FTP client. (It’s in the root of your domain).
The only element that should have a SEO URL is the link from the logo. From yourwebsite.com/index.php?route=common/home, you should have yourwebsite.com.
Here is how to change the link.
Search for the file: “/catalog/controller/common/seo_url.php”
Open seo_url.php and find “return $link;”
Before that line, just add a new line with this code: “$link = str_replace(‘index.php?route=common/home’, ”, $link);” (without quotes).
Save and upload the file.
SEO for categories.
For categories, from Admin, go to Catalog > Categories > edit on any category > Data > SEO keyword, write there something. For example, for the “cameras” category, just write “cameras”, your URL will be yourwebsite.com/cameras.
SEO for products.
For products, click to edit a product (from Admin > Catalog > Products), go to Data > SEO Keyword.
For example, for a Razer mice, you should write “razer-mice” as the SEO keyword. Your url for that product will be: yourwebsite.com/razer-mice.
Be sure not to use weird characters, separate the words with lines and not use duplicate keywords. If you have similar products, use numbers like “razer-mice-29”.
SEO for pages.
From admin, go to Catalog > Information > edit on a page > Data > SEO keyword.