Rise and Fall in the Modern Waltz International Style. Stand against a door frame and measure your height. If you are six foot and raise your heels you have risen from a position of where your knees are slightly flexed by about two inches. A five foot person
who understands the technique starts with the maximum lowering he can manage., say two inches. Now he can rise past his natural height plus two inches. From the other end of the floor who looks the best. Again as mentioned before, do all your lowering on the last beat of the bar of music you are leaving. Thats right you are at your highest and your lowest on the third beat. Don't go any lower on one than you are already, lest you dig yourself into a hole that doesn't look too good as you try to climb out.

Hi Quickstep
This point about lowering on beat 3 and not going any lower has been made before (by yourself i think, and also others)and the technique books do only mention lowering on 3.
The topic fascinates me because i love waltzing.
But here's a point to ponder. The 'look' of the rise and fall in waltzing should be a gentle undulating movement - a sort of 'wave' motion up and down (someone pointed out that in foxtrot it's the same, but a shallower wave - that was a good visualisation)
If the lowering all takes place in the same beat as the highest point (beat 3)then it's hard to see how this would produce a gentle undulation.
The 'lowering at end of 3' possibly refers to the conscious dropping onto the heels at the end of 3, but then with the long stride of beat 1 (into a natural turn, for example) there will be more lowering from the simple mechanics of keeping the legs soft, but now they're spread apart.
Thinking about the rise and fall of the natural turn (and other figures) and visualising the 'gentle undulation' required, it would seem that lowering at the end of 3 would have to be followed by some lowering during beat 1, which is maintained during at least some of beat 2, rising at the end of 2, continuing to rise on 3, then lowering on 3.
The shape obtained by strictly lowering just at the end of 3, then not lowering or rising during 1 and 2, then rising during 3 - this wouldn't be a 'gentle undulation'.

The leg division into 1 should not cause your body to lower. Remember that as the moving foot passes the standing one, the standing heel will come up - this lets the standing ankle help maintain body altitude. Between 1 and 2, a similar rising of the ankle is also what begins the swing.

"The leg division into 1 should not cause your body to lower. Remember that as the moving foot passes the standing one, the standing heel will come up - this lets the standing ankle help maintain body altitude. Between 1 and 2, a similar rising of the ankle is also what begins the swing."

I have to correct my previous post based on new information.

At the completing of step 1, we must start the upswing by raising the heel before the moving foot passes on it's way into step two. This is why the footwork is given as HT - initially heel, but toe by the end of the step which is defined as the time the new moving foot passes.

However, I was wrong about the case between 3 and 1. Here we are actually just finishing the lowering at the end of three, so we do not want to create rise yet. As a result, the standing heel will still be down as the moving foot passes, and will come up only a little before the moving foot pops up into its heel lead. This should have been clear because the footwork is TH - the heel is still in contact when the moving foot passes, wheras my version would have been listed as "THT", which it clearly is not.

This does unfortunately ruin my "easy" advice for how to avoid double lowering. The best I can say is to make sure to lower complete on time, and make sure to really actively use the foot as you prepare the step. While the heel stays down, the weight obviously still moves very far forward in the foot, to support your body until the moving foot is in position to take weight.