Not very. If you can do an hours walk then you can do this. It's only when it's very windy that the trip becomes quite strenuous. And if it's very windy we don't go out.
Will I fall off?
The kayaks are extremely stable. About two people a year fall in and that's usually because they are messing about.
Is there a weight limit?
Yes, 110 kg per kayak.
What must I bring?
Wear shorts and a T shirt. A hat and sun cream and a jacket for those cooler days. You can go barefoot it is up to you - your feet shall get wet! Also bring a towel and a change of clothes for afterwards - just in case!