Starting is much much much harder than continuing. If you've made the decision to write, it's better to post something, anything, to get on a roll. For example, today I posted a book review[1] just to keep on a writing stretch. It's not my finest work, but it's enough to keep me going.

[1]: http://bugsplat.info/2013-05-25-book-review-tubes-a-journey-...