While link shortening is automatic, it is not overly necessary these days. We only do link shortening to provide you with more tracking and features like link framing.
Instead of using the link shortener we provide, vanity URLs are possible. If you're interested in a vanity URL, please contact support.
You also have the option of connecting your bit.ly account and using that as your link shortener, but if you do, features such as link framing will be lost. To do so, click on "Connect Profiles":
Then scroll down and select bit.ly and follow the prompts on your screen:
When you are scheduling your post, you can disable the default link shortener we provide to publish the original link, but features such as link framing will be lost.
What about Twitter? For Twitter specifically all links, regardless of length are counted as 22 characters (http links) and 23 characters (https links). Included image counts for an additional 23 characters.