The only way to gamble without losing (ever) is to not gamble. Any other answer is wrong. If you want a 99.99% chance of making a profit you need to make a really really safe bet and once you one ONCE, walk away.
Even you are going to bet once and after winning walk away, you need to have control to yourself. Because that will give you excitement that you wanted to gamble again. And there is no other way to gamble without losing, unless you are not engaged with gambling then you are safe in losing. Just gamble small amounts to prevent big lose.