I've learned some interesting "one-line-frameworks" that just seem to make my life easier and guide me through different situations. I started to use most of them in a business context but transfered them to various social and family situations over the years.
Here are my two favourites. The first one is "Angry people demand, professionals require". I picked it up some years ago and it works like a mirror for me. In stressful conflicts, it reminds me to anchor what I want to a requirement. It helps me communicate why I need what I ask for, not just command and demand. Often I reverse my requests completely when I notice I'm just angry and I don't really have a solid base for what I'm asking.
The second one is the "Gap of Suck" which I first read in a book by Kathy Sierra. The idea is that most new skills require you to work through the Gap of Suck, the initial zone where you feel overwhelmed and stupid. Be it a new programming language or paradigm, a new sport, gardening – this model encouraged me to work through the first ugly and foggy hours of learning a new task.
Do you use similar mental models or frameworks?