It will not always be possible to make arrows from one variable to another. More often they will need to be made from a pair of variables to a pair, sometimes from a triple to a triple. To determine their number, you should look at what variables are repeated in two lines of the system. It is on them that the arrows of a specific equation of the system will be made.
Consider a specific example.
In this system, the variables x2 and x3 are repeated in the first and second lines, and the variables x3 and x4 are repeated in the second and third lines. So for the second equation there will be a mapping of a pair of variables into a pair (x2x3 to x3x4). Compose arrows (reminder: the arrow is drawn if the expression is not inconsistent with the specific values of the variables).
Since the equations are of the same type, all equations, starting with the first one, will be displayed pair by pair. Compiling a table.