my perspective
Stay away from married women, it is just not worth it
If you insist, however, here's my perspective:
There are three types of married women
1) Those who don't cheat
2) Those who do cheat, and pursue sex outside marriage
3) Those who are willing to cheat, but will give token resistance for a while so as not to feel like a total slut, i.e they will succumb eventually, but will not make it easy at first so they can soothe their consciences after by patting themselves on the back and saying "At least I put up a good fight."
Scratch number 1. Number two will let you know exactly what she wants. Number three takes time, according to how strong she is. Could be days or months.
The ideal conditions to seduce a married woman are:
1) You don't know her husband, and vice versa.
2) You don't live too close to her, and don't bump into her very often
3) She knows very little about you
4) She has no children
5) She doesn't see you as a 'real' person.
The last one is tough to explain, but that's it. You have to appeal to her sense of fantasy, of adventure. You have to be a mystery to her, a man who holds the promise of a sexual adventure. I'm sure someone else has covered this more in detail, but that's my take.