First you need to go to the blog like tumblr, blogspot, or wordpress..
Then, you sign yourself up there.
After you sign up, you'll see this page. You need to click the button I told you to click on the below picture.
After you click that, the interface will be like this
And the last thing to do is write the title, as for me I chose Caramel Macchiato, and the address, as for me I chose xiezhiyanyan.blogspot.com
About the template you can choose one of the templates provided by blogspot.com
Or you can make your own using the "Edit HTML" area. Then it's ready. ^^