What do you need to stop planning and start doing?

Sometimes you just need to go for it.

Planning something, rather then doing it, can feel easier then the actual act. Its more theoretical and can feel less risky. However we can only plan for so long before we put "pen to paper" and see if the result is worth it.

I could of continued planning for weeks... months... but finally I just had to do.

What do you need to stop planning and start doing?