At the risk of opening a can of worms, the easiest way to do it is the same as that recommended for a lot of cars.
Get someone to push the kickstart down gently, just so resistance is felt.
This pulls the chain in the direction of rotation & leaves any slack at the rear of the motor.
Undo the adjuster etc & you're done.
If I tension the cam chain using the kickstart method, do I need to turn the engine to Nr 1 TDCC?
While this sounds reasonable, I submit it will not absolutely result in a properly tensioned chain. If you loosen the tension bolt, then put a small screwdriver in the back of the tensioner you'll hit the end of the tensioner push bar. Now while you turn the engine over using the kickstart or the ignition nut, you'll feel the tensioner push bar go in and out A LOT. Some places have the slack on the back row, others have the slack on the front row. Depending on how the valve springs are pushing on the cam. Just because you are attempting to roll the engine forward does not guarantee slack in the back. If you just tighten the tensioner down at some random point, you could be locking all the slack in the front and it will be LOUD, or something in between.
This may be a characterisitic of the SOHC vs the car, but that's the way it works.
So the only way to be absoutelly sure you have ALL the slack at the optimum position is to use the #1 TDCC method +15°. And if you do, you'll be happy with the quiet sewing machine quality of the chain sound.
