Choose Your Own Destiny in Chinese / Japanese...

選擇自己的命運 means “Choose your destiny” or “pick your own fate” in Chinese.

Let's break down the words in this phrase here...
選擇 means to choose, pick, or select.
自己 means oneself or one's own.
的 is a possessive modifier.
命運 means fate or destiny.

我命由我不由天 is often translated as “The one that shapes my destiny will always be myself rather than the God” or “Rather than Heaven, I am the master of my fate.”

Breaking down the words directly:
我命 = My fate/destiny
由我 = depends (on) me
不 = not
由天 dependant (on) Heaven.