~ Maybe only for safe bets we can take a little profit from our bets. For example we want to bet in football when the position has reached 3-0 between a strong team with a weak team. this will most likely be profitable. So all that's left is to prepare a balance to wait for a match like this. So in this case the gambling secret is to provide a rather large balance to place a bet on the match.
I can imagine what a payout can be for such a bet. If you risk $1,000 to earn $10 in the case of winning, I don't think it can be called a safe bet. Actually there is no need for waiting this situation in football, you can go to a dice site and roll with 98% win chance. Just once. Yes, it is very likely that you'll win, but I wouldn't recommend to do that because, as I said above, no way it's a safe bet
I wouldn't call that a safe bet either
However, if you have enough money in your balance to play the same game again and again (like over 1000 times), it will be a safe bet overall as you will soon see that the outcomes of your bets quickly approximate to the house edge. With so high a multiplier you are not going to see a lot of variance anyway, so you would need a rather small sample size to get there (safe game by and large)
Ironically, while rolling once is a far cry from being a safe bet (which I totally agree with), rolling 1000 times (and more) is pretty safe as you are unlikely to lose more than the house edge in the end. It is as unlikely you will be able to earn anything indeed, but as far as safe bets are concerned, that's pretty much it. In fact, it could be the exact thing you might be looking for (as in contests or something similar)