The analogy of a "Roller Coaster" is often used to describe out-of-control diabetes sugar management.
Here is one I came up with to portray the theory behind properly-controlled glucose management. The following describes the "feedback mechanism" which a ship's captain uses to steer the ship. It is the theory behind many control systems and servo mechanisms.
Here's a description of the "feedback mechanism" used in steering a ship:
"When the boat deviates from the present course, say to the right, the steersman assesses the deviation and then countersteers by moving the rudder to the left. This decreases the boat's deviation, perhaps even to the point of moving through the correct position and then deviating to the left. At some time during this movement the steersman makes a new assessment of the boat's deviation, countersteers accordingly, assesses the deviation again, and so on. Thus he relies on continual feedback to keep the boat on course, its actual trajectory oscillating around the present direction. The skill of steering a boat consists in keeping these oscillations as smooth as possible.”
So starting today, instead of thinking of yourself as the helpless Roller Coaster passenger, think of yourself as a ship's captain. When you're either "high" or "low", assess your deviation and countersteer. Try NOT to oversteer. At the same time keep making new assessments of your position. Rely on "continual feedback" to keep your boat on course and keep your "oscillations as smooth as possible."