If you want to make a sharper turn than is possible using the rudder in a K1 or edging in a sea kayak, you could use a forward sweep. Using single or multiple forward sweep strokes will keep you moving forwards but will turn you quite quickly. It can also be combined with other strokes for even faster turns or for turning on the spot, when combined with a reverse sweep stroke.
The forward sweep stroke starts with the blade in the water in a similar position to the start of a forward paddling stroke: close to the boat and as far forward as you can reach by rotating your torso (not by bending your body forwards). Your top hand is much lower than for a forward paddling stroke though and you sweep the blade in an arc away from the boat, unwinding your torso, which provides the power, and keeping your lower arm straight and the paddle shaft fairly horizontal so that the blade is quite far out from your kayak. The first part of the sweep is the most important and powerful, so it’s not always necessary to sweep right around to the stern of your boat, especially if you’re in an unstable K1.
People are often taught to watch the paddle as it arcs around to emphasise rotation. However I feel that you should always be watching where you’re going so I think it’s better not to do this.
To improve stability during the sweep, you can angle the top edge of the blade slightly downwards. If you need to do multiple sweeps, it can be a good idea to skim the back of the blade across the water as you bring it forward for the next stroke to maintain stability. A refinement for sea kayaks is to edge towards the paddle which will increase the speed of the turn.