Flat water is where most paddlers start, and the skills developed there transfer to everything harder. The techniques that make a flat water paddler efficient, good posture, effective blade angle, proper rotation, are the same ones that matter in moving water and coastal conditions. Getting them right early makes a significant difference.
Posture and Seating
Sit upright with your back away from the seat back and your hips slightly forward. Most beginners slouch, which reduces the range of motion for the paddle stroke and puts more load on the arms. Paddling is mostly a core and shoulder movement. The more upright you sit, the more you can rotate your torso into the stroke and the less your arms have to do.
The Forward Stroke
Enter the blade fully submerged near your feet, pull through to your hip, then exit cleanly. The exit is where most beginners lose efficiency by pushing water up rather than letting the blade come out cleanly. Rotate your shoulders through the stroke so the work comes from your torso rather than your arms. A proper forward stroke at a sustainable rate is more effective than a short inefficient one at high rate.
Going Straight
In a kayak, alternate strokes on each side naturally keep you tracking forward. In a canoe, the J-stroke corrects the natural turning tendency of a single-bladed paddle by adding a small outward flick at the end of each stroke. This takes practice to make automatic but is the key technique that separates efficient canoe paddling from zigzagging down a river.
Turning
The sweep stroke, where you draw the blade in a wide arc from bow to stern, turns the boat. A forward sweep on the right turns you left and vice versa. To turn sharply in a small space, combine a forward sweep on one side with a reverse sweep on the other. These are the fundamental turning techniques and everything else builds from them.
Before Moving to Harder Water
Before moving from flat water to anything with current or swell, be confident in wet exits and re-entry from the water, not just staying upright. Knowing how to get back into or onto your boat after a capsize changes your relationship with the water fundamentally. Practice this on calm, warm water in a controlled setting.