How do you ensure that there are no losers in a game?
Agree to modify the rules?
For example, suppose you have a small cake which is to be shared between two people. Assume both people would like as much cake as possible.
If the two people simply take it in turns to grab as much cake as they like then the first person's winning strategy would be to take the whole cake, leaving the other person without cake.
Alternatively they might agree to follow "I'll cut, you choose", whereby the first person divides the cake into two parts and the second person chooses the piece they will get.
This becomes more complex if the cake has various toppings, especially if the participants value different topping differently.