Well, almost.
Hot to the receptacle - You have that.
THEN NEUTRAL to receptacle from your NEUTRAL bus.
THEN GROUND to receptacle.
Wire your plug for the element accordingly. Hot to hot, Neutral to neutral, ground to ground.
At the element, HOT to one side of the element, it doesn't matter which side. Then NEUTRAL to the other side. You want the ground to be connected to your kettle. That will give you an equipment ground. So if there is any leak of electricity it will flow to the path of least resistance, i.e. the ground wire and not you or whoever may touch it.
Your confusion is likely the result of looking at Kal's material and not noticing that he's using 240v which has 2 HOTs and a ground, but no neutral whereas 120v has 1 HOT, 1 NEUTRAL and a ground. Get it? (each HOT wire in 240V is 120v)