A good (ballroom) exercise is to swing the leg back, from the hip, articulating the ankle joint early in the movement, such that the tip of the toe only is in contact with the floor, and the shoe perpendicular to the floor.
The forward movement of the partner determines the length of the back step, and the foot only rolls through the toe to the ball of foot at the extent of the stride, when weight transfer occurs. It is a very common fault to step directly back to the ball of foot, but as a corrective excerise the leader can be asked to vary the length of stride, over a wide range, obliging the follower to follow. The habit of just extending the toe back, without weight, is one well worth cultivating.
Compared with 'Latin' walks (particularly in Rumba) the walking movement is quite different, mainly arising from the absence of 'swing' in the leg. The foot is in contact with the floor throughout, calling for quite different useage of both knees and ankles, and pressure into the floor.