You don't.

All jokes aside, there are three things that you have to remember with women:

Rule 1 - Involvement with women will usually be a net negative for the man.

Women will generally not involve themselves with men who they cannot derive some form of benefit from. They have too many options available and their strategy relies on picking and keeping the best man that they can.

What that means for you is that you will have to lose something in exchange for her association. The thing you want to do is minimize your loss and maximize your return. The ultimate loss is, ironically, marriage (which is why women push for it when they find a man that they deem suitable.) The ultimate gain is having to give as little as possible for continued sole access to her body. Most relationships are somewhere in the middle.

Only you can determine what level of ROI is acceptable for you.

Rule 2 - Briffault's Law

Women will not honor any agreement where they get the benefit up front with a promise of reciprocity at a future time. Should you attempt to force them to honor it, they will either hold the reward hostage for more benefit (as seen in a lot of sexless marriages) or they will end the association now that the value has been extracted.

If you enter into an agreement with a woman, make it overt and demand her end up front. Do not rely on a woman's integrity or sense of obligation to fulfill an agreement unless she has demonstrated those qualities in the past. Moreover, never let her have the impression that she has gotten all the value from you that she can get.

Rule 3: Don't listen to what they say. Watch what they do.

Women lie. They are experts at lying to others and even to themselves. They will lie about their motives, their desires, and their expectations. They are experts at manipulation and ply their trade as easily as breathing. Moreover, as men, we are easy to deceive because of our attraction to them.

Watching what they do is the best way to discern their motives. Most people, but especially women, are not self-aware enough to mask their actions when an opportunity to move towards their goals is presented. That is why a woman will lie about the kind of men she is attracted to, but then put herself in positions to meet and consort with those very same men.

Watching what women do can tell you how she feels about you. She says she misses you, yet she never returns your messages promptly? She says she is "working on herself" yet she's still following the same patterns and associating with the same people? She complains to you that she's "always broke" yet finds money for alcohol and cigarettes? Her actions are her intentions, and her words a ploy used to lay a false trail for fools to follow.