There doesn't even have to be a specific "method" to it
It starts after the stress immediately following her first kid or perhaps after a major life event puts her behind, and you support her through it. No obligations, just taking care of her needs, holding space, understanding, buying her as much time to relax as possible
As she starts to feel better and develop free time of her own, ask her to help with small tasks. Laundry. Dishes. Show her exactly how you like it done. Care that she does it right—check like it matters—and reward her with affection and gratitude each time - a "thank you," a touch, a grope, a kiss. And rarely, but often enough that she senses it could happen at any time, pull her arms behind her, bend her over the counter, and use her cunt, her mouth, or put a Hitachi up to her clit and tell her what a good girl she is
Buy her dresses that flatter. Praise her appearance for specific things that attract you that she has control over - her style, makeup, hair, shaving, how she wears accessible panties (or none at all).
Solving problems together, listening closely to her needs, desires, and frustrations, providing security and safety in a real, challenging world... and when the kids are out at school, and her belly is swelling with the next one, tying her up and using her like your personal fucksleeve
And five years later, or ten, or a lifetime, when she realizes that in her thoughts, she calls you "Sir," when she catches herself moaning "thank you" while you play with her, she'll stop and wonder for a moment when it happened. When she became your good little housewife. And then your cock slips into her mouth and the question fades away as she loses her train of thought...
All she knows is she said "yes" every step along the way.