One Day Means Never While Day One Means Getting Started
Do you often say one day or do you get started and look at it the project is day one. Too many times it's easier to say one day you'll do something rather than just getting started. There's never a perfect time to start to do something and you should look to wait to see when that time comes, because you may never be ready when the time really comes.
By making it day one and getting started on a project you can look at it as a learning curve and make mistakes along the way. That way, you know you are on the road to success and you don't have to wonder what would've happened if you'd done what you wanted to do rather than waiting until the time was perfect to get started.