The idea here is to question what you're doing, and set criteria about the decision process as you go along. Psychology Today explains:
Research demonstrates that long before outcomes are known, asking employees to explain their decision processes can encourage them to conduct a thorough, evenhanded analysis of the options.
Process accountability can be applied to our own choices, too. It just means setting some criteria for the decision process in advance. Before arriving at the restaurant, you might agree that you’ll only wait for 30 minutes. Prior to choosing an employee to hire, you could decide how much training this position should receive.
So, don't just think about your decisions, but also think about how you're going to make those decisions, and how long you're going to spend on the process. When you're done, ask yourself questions about how you got there, and eventually your decision making process should improve.