Creation of a legged vehicle

I wish to create a legged vehicle similar to a mech in the films, I have created a custom character of the barebones of this vehicle however have failed to find a way to move this vehicle. Currently, the model plays its walking animation as CFrame seems extremely difficult, I have tried body velocity to make it move forward when the key ‘w’ is pressed but this method seemed very ineffective. Could anyone suggest a suitable method of moving this model, so that when the seated player presses a key it moves in that keys set direction?