This post is for the people having trouble with the exercise 4/7 Deploy a Website.
That works for me:
Step 1: Click "Get Help" in the bottom right of the page.
Step 2:write the following commands to the console.
$ jekyll new personal-website
$ jekyll serve (maybe not necessary)
$ pwd (just to see where are you are)
$ cd personal-website
$ git init
$ git remote add origin https://github.com/your-username/your-username.github.io.git
(this step only work right when you created the repositiory on git as told in the previous exsercises)
$ git remote -v
Hope that this may help some of you.