What are some of the key elements that go into making our dancing look light(soft) and easy.

One is soft knees

exactly - soft knees is top priority.
2)Perfect togetherness is important. This means good leading and following.
3)Also, perfect balance at all times.
4)sensible (not exaggerated)use of body sway, as this gives turning actions a 3-dimensional aspect, minimising the appearance of stiffness

In standard top line should have tone but not be tense or stiff.

Turning the correct amount between steps so there is no stopping and starting of the body rotation or movement. Flowing from one figure into another so they all look as one.

Use your feet and ankles as well as the knees. If it is Quickstep you should have a higher contact point than if you were doing the Waltz or Foxtrot.

Smile ? It always makes a couple relax and look as though thay are not working.

Jane you are so right. I think this is more impotant than soft knees. When we don't smile we are more likly to overwork not letting our body do the work for us by move the body naturaly.

Onlooker could you explain how we use our legs and knees to dance softly,thanks Dave

Dave. Use of knees is the most easy to explain in a Foxtrot. Go down the hall either backwards or forewards. Going forward. as the weight arrives over the front foot the knee will bend or flex forward. Backwards, as the weight arrives over the back foot the knee will bend or flex forwards. That's right ,forward is to your own front. The amount that the knee bends depends on the individual. The more the bend the more energy is built and stored then used. But you must never dig a hole you can't get out of. Waltz can have more bend. Quickstep less for obvious reasons. This dance it is advisable to have higher contact point and very toned feet and ankles. If anyone has a tape of John Wood dancing the Waltz. As he steps into a Reverse Turn with the left foot the thigh is almost horizintal to the floor. The weight at this point is divided. The rear knee I would say is about ten inches from the floor and pushing. He seems to have a never ending rise. A friend of mine once asked Richard Gleave how low can I go. The answere was as above, there is no rule as long as you can get up and still be dancing.