Approach your partner and mention you would like to try this idea. Let them know they don’t have to do anything, but that you will do all the work. You technically do not need their permission, but they may be offended if they find out about it after the fact, so it’s always a good idea to get consent first.

Whenever you learn something new about your partner, write it down either in a journal or online in a document. With each argument, with each gentle discourse, notate special traits about them. Keep it as a live document to update and record favorite foods, reactions to gifts, and what the other person doesn’t prefer. You can also record how, when you approach them when they were angry and found it easy to communicate and when you didn’t. And you can ask deep questions like, “what do you think is your purpose in life?”

The key to making the Operating Manual usable is to be able to organize all the information so that it is easy to retrieve when you want to.  

When you record all this information, you are able to peruse it and reflect on it at any time. This will help you discover what the true motivating factors are of your partner, what turns them on, intrigues them, and what doesn’t. For example, if you have in your operating manual that your wife doesn’t like surprises, you will more likely remember not to do things that she may perceive as a surprise.