I used to play dice in online casinos and apply the martingale technique. In the beginning, I had some profit but as the time went by I started losing and losing and I wasn't able to cover my initial bet.
Now I am trying something like the same but differently. I pick a big football club and I bet that it will lose. If I lose my bet, I double it and so on.
Martingale is not a good way to earn the easiest profit yet you can lose your funds faster than playing it with a smaller bet. Martingale is just good when the odds are upon you but not a good strategy if you are losing. It makes it worst in the long run so I wouldn't suggest that.
Just look for a better odds the team and bet some 60% of your main funds or so.