What is the solution to this problem in which the goal is to find the best strategy

Question

"There are two prisoners and a jailer who wants to kill them, but in an act of magnanimity the jailer tells them: At your side there is a room with a chessboard wherein each square there is a coin placed randomly (heads or tails), I will enter with one of you to the room and I will point out a square, the square of life, the one who enters with me will have to change a single coin of the board. Then we will leave and without speaking or making any gesture, the other prisoner will enter and will have to guess which is the square of life. Now, before entering with the first prisoner, you can agree on a strategy".