I have been researching and contemplating the subject of "passing" for 15 years. Here are the results of my years of experience.
Passing requires three rules. These are:
1. Dress appropriate to the environment. Are you going to the grocery store? Or the opera?
2. Dress appropriate to your age. If you are a 45-year-old GM, dress as a 45-year-old GF. Sorry, but this is a "tough love" message to the community.
3. Use body language that conveys that today is an ordinary day just like any other. You are just another woman getting through the day (and life!) like the rest of us. Behave that way.
If you can nail these three things, you pass. Everything else falls into place. Everything else is just details.