First, you always spy.
Second, you monitor public information to determine enemy tactics and develop wargames around those strategies.
For instance, anti-aircraft strategies against the USA changed radically as the USA launched preliminary drones to set off Iraqi radar stations then launched cruise missiles against all known pings.
SomeAmateur@sh.itjust.works 23 hours ago
War gaming, which is basically thought experiements with some rules and writing down results.
If red team had this stuff and blue team has that stuff what would you attack and how would you defend it. If you lost it what would you do to make up for it?