“ If you take a lot of chances, that adds up eventually and you'll have some big wins. Just do it safely, so that they don't add up to a lot of big losses, too.”
“Just” do it safely. If it’s safe, you are not really taking chances.
"safely" is shorthand here for "with an appropriate degree of safety net and recoverability". There is a whole spectrum of risk between "only carrying activities that are 100% certain to succeed" and "trying anything, absolutely anything, with no thought given to how I'll react/self-protect if things go wrong"
“Just” do it safely. If it’s safe, you are not really taking chances.