There is a safe way. Never play with emotions or impulse. Never go all in with your total bankroll. Have good money management, split your bankroll and bet with amounts that are 1/15th of your bankroll, that way when you lose you still have many more to place and become even at worst case. Knowledge in what you bet is also needed, bet on things you know like players and many other factors. You only need to win 55% of the time and be at a small profit, over time that adds up. I have bet for 2 years and I am at a small profit of 2 bitcoins, however I have had many risky games parleys of 6 games where only 1 loses, so if I played safer I would be at a bigger profit. Bottom line is you have weeks and months where you lose and weeks when you win, as long as you manage your money good you should be even at worst case.
you are able to win cause you have good prediction. This is not by luck, but if you talk about dice game or other table games, you realise it is very hard to win since everything is based on luck.
Absolutely, do not rely on luck if you want the safest way to gamble, made some good research on how to win the game. Remember to have a good control of your self you will have always a good decision making. Bankroll management is very important key to be successful in gambling.