When you have created at least one parameter in your animator, you can add conditions.
By clicking on a transition arrow in your animator view you’ll see in the inspector window a “Conditions” Tab.
Add a condition by clicking on the “+”.
It will automatically fills the condition with your only parameter available, or give you a list if you have more than one parameter.
The you’ll have to choose the logical operator and fill the variable with wanted values to allow the transition from a state to another.
In our example video above, we have for the “player_speed” float parameter the condition : “player_speed parameter greater than 0”.
Meaning when the “player_speed” float will increase, the idle animation state will leave room for our walk animation to be played.