Make sure you’ve activated the theme before importing.
Step 1 : Log into that blog as an administrator.
Step 2 : Go to Tools:Import in the admin panels.
Step 3 : Choose “WordPress” from the list.
Step 4 : Upload this file using the form provided on that page.
Step 5 : You will first be asked to map the authors in this export file to users on the blog. For each author, you may choose to map to an existing user on the blog or to create a new user
Step 6 : WordPress will then import each of the posts, comments, and categories contained in this file into your blog