Write the scene in which the heroine and hero meet (or meet again) within the first few pages of chapter one.
Invent a reason why the two main characters struggle to be together, despite their obviously wild attraction to each other. Clarify that reason at some point in the first chapter.
Write a number of scenes in the first half of your novel in which the characters emotionally circle each other, taking a figurative step toward each other, only to back away in frustration or misunderstanding.
Plan a brief, romantic interlude for your couple, including a stolen kiss or moment when they are alone.
Pay close attention to your dialogue as it will keep your reader engaged. Practice creating pithy exchanges, arguments and misunderstandings between the two characters, and introduce some normality and humor into the dialogue. You want your readers to like your characters, and both pluckiness and humor are endearing traits.
Write that first bodice-ripping love scene about one-third to halfway through the book. This is the first payoff for the reader. Although it may feel awkward or even embarrassing, well-written love scenes sell books. The more believable you make a love scene, the more readers will enjoy your book and clamor for more.
Provide your reader with an emotional payoff teaser by allowing the couple to be temporarily happy together, even if it's only for one night.
Write more scenes in which the characters revert to emotionally circling each other, despite the fact that they've declared their attraction to one another. Relationship and situational conflict should be the plot drivers of your story.
Create at least two more love scenes to increase the pacing, as the latter half of your book is where the reader must feel as if she cannot put the book down, precisely because the pacing, love scenes, dialogue and plot twists are clipping along at a faster pace. If you space them out evenly, you will create a payoff-suspense-payoff-suspense arc that keeps your reader engaged.
Write the pivotal plot scene in which the characters' misunderstandings rise to a crescendo, and your heroine and hero seem forever destined to remain apart --- whether the conflicts are internal, other-woman-related or a combination of both.
Determine how the over-arching conflict will resolve itself in the pivotal crisis. Either during the crisis, or just after it is resolved, your heroine and hero will admit their true love to each other, and they will commit to each other forever. The proverbial happy ending is key to the success of your bodice ripper.