I always prefer betting on sports I have deep knowledge on, for instance tennis. After big losses, I will stay away from my favorite bookmaker and wait for a week, and try to find the perfect spot to place a bet. I know it sounds silly to say but there are some very safe bets if you are patient enough. When I say safe, please don't take it literally, we all know it does not exist in real life, or else your return will be extremely small.
Finding the best site to bet on based on odds is a smart thing, but I couldn't understand what does it matter if you bet on spots that you have knowledge on, or you bet on sports that you don"t have any.
At the end, the sportsbook always has an adventage over you, and the chances to lose at both cases is the same.
There is nothing called safe bet.
Betting is not safe , not matter what are you betting on and what are you chances to win.
It is litteraly not safe and could be counted as a very risky activity.