SEO All In One Pack post not available

I have the SEO All In One Pack and when I make a post I have option to put in tags and categories, but it is not within SEO. My problem is that I do not understand how it works. After the post is completed and I click on All Post, tags and categories show of course, but under the headings of SEO Title, SEO keywords, SEO descriptions there is nothing there. Where do I input this. It does not appear anywhere for me to input within my post fields.