As you've already installed tomcat, java and postgresql, you are close to complete the task.
- In your step 1, you are defining the environment variable for postgresql.
- Step 2 is about configuring the two bat files (namely thingworxPostgresDBSetup.bat and thingworxPostgresSchemasetup.bat) - where you got to open and make sure you have the correct *tablespace_location, user credentials etc.,
- Step 3, As you've configured the scripts (in step 2), now you got to execute the files using 'Run as Administrator'. It should prompt for 'twadmin' password.
Let me know if you are stuck at some point and facing some issues/errors.
*Note: the tablespace_location should be updated with the location of ThingworxPostgresqlStorage directory. i.e., in windows - C:\ThingworxPostgresqlStorage