Nothing that has to do with gambling is safe.
There are methods as to where you can limit your losing gambling.
You could have certain strategies to limit those.
Yeah, that is something we need to accept and understand that there is no safe method in gambling. The only way we can stay long in gambling is just to play it for fun, we need to understand that we do not have the chance to win, so it is better to play it for fun and nothing else.
but i think there is no fun in gambling without money investment, therefore to me the only safe method to play gambling is to invest such an amount money in gambling which you can bear to lose. and never try to exceed that limit.