Plotting books is an ever-changing process for me. I started out as a plotter-style of writer. That is, I outlined excessively, followed character sheets, and generally did things in a linear, regimented way. I realized that writing the book wasn't as much fun as plotting, that for me the excitement came from the story first unfolding.
That realization inspired me to try the pantsing mode of plotting. I start with a germ of an idea. If its a mystery, I invent four to five characters who could have killed the victim, then I write the book as if each one killed the dead person. I don't know who-dun-it to the end. What fun I'm having now as I write. I practically leap up and run into my office each day.
Plotting a romantic suspense is a little trickier. I can't wing it in a totally pantser kind of way. Instead, I have an idea bank of events that will make the romance better and worse and also the suspense better and worse. I mix and match the ideas at will. Then I have to be exceptionally ruthless on editing to make sure each scene does double duty.
Here's the thing. You can have the best plotted book in the world, but if you aren't excited about your characters or what you're writing, it's unlikely that your characters will be memorable. Translation, another rejection letter. Editors, agents, and readers won't care about your characters if you don't. Find the method of plotting that excites you, and stick to it.
No Second Chance, winner Stepping Stones Magazine cover contest
House of Lies, winner, Best Romantic Suspense