This is the moment in your story when the reader gets the big payoff. It only works if you skillfully lead up to it. For instance; it isn’t just the time of the big fight between the hero and villain. The climax leads up to a struggle on a cliff and the fall and demise of the villain. The climax is not just the villain falling off the cliff and dying. It is all the action that gets us to that point.
The hero realizing the heroine didn’t show at the rendezvous spot because the villain kidnapped her. The hero rushing to save her before the villain can get the heroine to a shady preacher who will marry them even if the heroine is gagged. To add tension we can have the couple married but our hero arrives before the heroine can be deflowered. The big fight between the men is just the culmination of the climax.
Don’t think of the climax as when the hero and heroine kiss and say I love you…..finally. Have it be those moments leading up to that big event. In the Princess Bride, Wesley storms the castle, finds Buttercup, fights a war of words with the Prince, and wins the fair Buttercup. All of that is the climax. The kiss at the end is the reward for living through the climax.
If you set up the climax right it is so tension-filled that the reader will need a break afterward to enjoy how traumatic the moment was and how lovely everything worked out now.
Remember to ratchet up the action or emotions to a peak before the actual climax to make the payoff worth more. Keep them turning until the very last page.