If you found an interesting post on Facebook, share it with your Tumblr blog followers by creating a new text post. Alternatively, add a link to your Facebook profile or page by editing your blog's description.
Share a Facebook Post
By grabbing a post's embed code on Facebook, you can share that same post on Tumblr while keeping its original formatting and features, including the "Like" button.
If the linked Facebook post's privacy is not set to Public, some of your readers may not be able to access the linked content on Facebook.
Click the downward-pointing arrow next to the Facebook post you want to share and select Embed Post.
Copy the embed code to your Clipboard by selecting it and pressing CTRL+C.
Visit your Tumblr Dashboard and click the Text button to create a new text post.
Selecting Link lets you link to a Facebook post without displaying the original formatting.
Open the cog menu and click Rich Text to open the Text Editor drop-down menu. Select HTML.
Paste the embed code in the body of the post by pressing CTRL-V and click Post to publish the post on your Tumblr blog.
Tumblr does not display the embedded post on your Dashboard. To see the post, visit your blog by entering its address -- in the X.tumblr.com format, where "X" is your blog's name -- in your browser.
Adding a Link to Your Facebook Profile
Display a link to your Facebook profile or page at the top of your Tumblr blog by editing its description.
Open the Account menu and select Edit Appearance under your blog's name.
To edit the description of one of your secondary blogs, click the blog's name, reopen the Account menu and select Edit Appearance.
Click the Edit Appearance button.
Enter <a href="My">http://www.facebook.com/johndoe">My Facebook Profile</a> in the description field. Replace johndoe with your Facebook username or with your page's custom URL and -- optionally -- My Facebook Profile with the link text you want Tumblr to display.
Save your new description by clicking the Save button.