Seth Godin very well articulates a precise formula for starting up a venture:
Start your first business this way: Begin with the smallest possible project in which someone will pay you money to solve a problem they know they have. Charge less than it’s worth and more than it costs you.
Repeat.
You don’t have to wait for perfect or large or revered or amazing. You can start.
This may help overcome our initial fears and take minimal risk. The first plunge is necessary, in the safest possible manner – if possible.