Technique
All paddling disciplines share some fundamental concepts. In particular they all require power to come from the core, not the arms. To generate power from the core, you rotate your core forward, place the paddle in the water, counter-rotate to pull the boat forward, and exit. The exact manner in which you do that can vary a great deal.
Here are some general hints.
Recovery (forward rotation) - do not rush the recovery. Make sure your paddle and core move forward together. Keep an upright posture. Do not over-rotate.
Entry and catch (placing the paddle in the water) - Place the blade in the water and feel that it has a solid "grip" before you counter-rotate.
Pull (counter-rotation) - Your arms should not flex while you are applying the power. Maintain the "power-U" as you pull (see Heaver video and his "don't wrinkle the cellophane comments").
Exit - get the blade out of the water quickly so you don't create drag.
For more paddlng technique from an outrigger perspective see the videos by Danny Ching and John Puakea, Peter Heaver, and Chris Hill.