Ain't hard. You have all the tool you need in the owner's tool kit. There should also be instructions in the owners manual. Slack should be 35-45mm half-way between counter sprocket and drive sprocket centerlines. You can measure easily by placing a stiff piece of cardboard against the bottom of the swing arm and pulling down on the chain and marking the position, then pull up on the chain and mark the same point on the chain's location on the cardboard. Distance between the two points is the chain slack.
To adjust loosen rear axle nut. Your adjusters are different from mine so turn each the same amount to move the axle to the rear. Go slow, like one flat at a time because when you get close a little goes a long way.