Download Reactor and configure a mapping named “/reactor” which points to the "Reactor" directory. The reactorFactory.cfc file should be in the root of the "/reactor" mapping.
Note: If you place reactor in your application's webroot you do not need to create the reactor mapping. This will let you use multiple versions of reactor on different sites on the same server.
Create a database. I named mine "scratch".
Create a ColdFusion data source which points to the database. To reflect the database name I called mine "Scratch".
Create a directory under your webroot where Reactor generated files will be placed. I called mine "Data".
Create a ColdFusion mapping to the directory you just created. I tend to prepend the application’s name to the name of the directory. I named my mapping "/ScratchData".
Note: If your data directory is in your application's webroot you do not need to create the mapping.