When it comes the time to take a big decision you ponder and wait for the right moment. In some cases that wait may never end.
The will never be a perfect moment[^1].
If you wait for when you think you're ready to make the jump, you never will.
You need to take some risks in life. Being good means realizing when the risk is worth the payoff and when it's not.
That doesn't mean to jump when you don't have solid ground below you. Just that you'll never be 100% ready. Being 0% ready and being 90% ready is a world apart. Try to get as close as you can to ready and put yourself in a position that if you fail is not such a big deal and then just go for it. Decide and go. Give it all.
Of course, luck and variables outside of your control are always at play, so don't blame yourself too much if something doesn't work out. But also don't say on it's not my fault.
Try to analyze what went wrong and fix it for the next try.
[^1]: It might, but it's extremely unlikely. It's like just staying home doing nothing because you are waiting to win the lottery. Sure, it _might_ happen, but more likely than not it will not.