I define non-clinical anxiety as, "experiencing failure in advance." If you're busy enacting a future that hasn't happened yet, and amplifying the worst possible outcomes, it's no wonder it's difficult to ship that work.
With disappointment, I note that our culture doesn't have an easily found word for the opposite. For experiencing success in advance. For visualizing the best possible outcomes before they happen.
Will your book get a great testimonial? Write it out. Will your talk move someone in the audience to change and to let you know about it? What did they say? Will this new product gain shelf space at the local market? Take a picture.
Writing yourself fan mail in advance and picturing the change you've announced you're trying to make is an effective way to push yourself to build something that actually generates that action.
One reason this is difficult is that we've got a false humility that pushes us to avoid it. The other is that when we're confronted with this possible success, we have to confront the fact that our current plan just isn't that good (yet), that this site or that menu item really isn't as good as we need it to be.
If you expect rejection, it's a lot easier to ship lousy stuff. Said that way, it's clear that this is a ridiculous strategy. Better to make it great now rather than mourn failure later.
Go ahead, write yourself some fan mail, in advance.