To customize your site and make it your own; go to Dashboard -> Appearance -> Customize
You can always use the shortcut from your blog homepage by clicking on “Customize” in the top bar (you need to be logged in).
To change the header; go to Appearance -> Customize -> Header Image
Don't forget that you need one for web and one for mobile, you'll find the measurements in the "Header Image" section. These measures can not be changed.
You can create a custom menu in Appearance -> Menus. Once that you’ve created your statics pages, you can set a new menu, just drag the items to sort the position on the menu. Make sure that you’ve marked the Primary Menu field in the bottom of the page.
Don't forget to add your Social Media channels to the "Follow me on" section on your blog homepage; go to Customize -> Social Settings or Bloggers Settings in the left sidebar of your Dashboard.
You can change the font family using a third party service as typekit.com. Create a free account on typekit.com and search the font that you love. Once that you’ve your font selected, click on Use Font button:
A popup will appears, select web tab and create a new kit:
A new window will appears, name the kit and write your domain name in the second text field:
So, the ID will be cli0tof. Copy that ID and paste it into your site, in Appearance->Customize->Fonts (Typekit)
Write the font name in the field where you want to set each font. You can select as many fonts as you want in TypeKit site.