Your feed is the single most important tool for building your presence on Twitter. Your feed is a list of all the updates you make using Twitter.
Most of your tweets should reflect who you are professionally. Some people will advocate only using Twitter professionally, but if you are all work and no play, your profile will be dismissed as fake.
You need to balance your feed between your work and your play.
But always be mindful everything you post is recorded. There is no undo function on Twitter like there is with Facebook.