Now you've got your new Tumblr theme you'll want to install it right away!
Unzip your download folder and locate the Shift.html file, it will be in the root of the folder.
Now go and open that bad boy up in your favourite text editor. Don't open it in a web browser as it will look a mess. Instead right click and select Open... I use Espresso for the Mac. But there are free programs such as TextWrangler for Mac and Notepad++ for PC. Every PC comes with NotePad installed for free as well.
Using TextEdit on a Mac?
If you've opened up the HTML file in TextEdit it may have messed it up completely. Bad times. If you follow this guide: http://support.apple.com/kb/TA20406. It'll show you how to open HTML files properly within TextEdit.
Now you've got the file open, select everything within it either by dragging your cursor from the beginning of the first line all the way to the bottom, or by pressing CMD + A (Mac) or CTRL + A (PC). Now copy all of that selected code by going to Edit then clicking Copy or by pressing CMD + C (Mac), CTRL + C (PC). That code is now stored on your clipboard.
Log into your Tumblr Dashboard. Now that your logged into Tumblr click on the little Clog icon at the very top of the site. See image below...
Now select the blog you would like to install the theme on from the list on the left.
Now click on the Customise button. Geez Tumblr have made it long winded!
Finally! You are now on the Customise screen for you blog. Click on the Edit HTML button in the left sidebar. This opens up Tumblr's text editor.
Delete all the code in this area so it's nice and clean. You don't want to leave anything in here as it might mess up your shiny new theme.
Now go ahead and paste in the new code. CMD + V (Mac) or CTRL + V (PC) will paste in the code quicker than a flash. Or you can go up to the Edit menu item and click on Paste. Either way works fine.
Now hit the Update Preview image. You'll notice the preview on the right updates with your new theme. There might be a few issues as it will still be using your old themes options. So hit the green Save button and then click the grey Appearance button. Refresh this page now (F5 or right click and click Reload / Refresh). Now your new themes options have loaded in. Hit the green Save button again. Now go to your blogs page and you'll see the new theme is installed! Easy as pie, not as yummy though.
Now you can head on to the Customisation area of this document to find out how to make your theme look the way you want.
To create a custom page for your blog make sure that you are in the Customise screen. Follow the steps above to get to the correct place. Scroll down on the theme options sidebar and you'll see an 'Pages' button. Click on this and then click on the 'Add a page' button.
This then opens up the Add page pop up. Enter all the details you need for your new page. Here is an example:
Click the 'Create page' button when you're finished and then click the Save button. Your new page has now been created and a link has been automatically added to your main navigation menu.
To use ANY of the hundred of Google Fonts that are available simply follow these simple steps.
First off get yourself over to the Google Fonts directory and pick yourself a tasty new font. http://www.google.com/webfonts#.
Once you've picked a font click on the Quickuse button underneath that particular font.
Now copy the 2 elements highlighted in red in the below screenshot and paste each part into the themes options.
Paste the link and the font name in the theme options here: