Identify the most significant variables in your system. This can include stakeholders, raw material sources, production facilities, disposal sites, etc.
Where one exists, identify the relationship between variables including important details such as direction of influence. Is the influence between variables A and B, for example, unilateral? Bilateral? Does A act positively on B (e.g. as A increases, so does B)? Negatively? Indicate the direction of influence using positive (+) and negative (-) signs. Go through this process in each instance where there is a relationship between variables.
Identify feedback loops and classify/label these as either reinforcing or balancing loops.
Review your causal loop diagram for any system archetypes – do you see any familiar patterns? If so, identify these.
Are there any feedback delays? These are important to identify when thinking about the dynamics of the system as well as potential leverage points.