You can use the below post to set up the same! You can use Adobe I/O to
set up things easily.
We're facing the similar issue with Brand Portal integration. The client
secret keeps on dropping and we noticed that the older bundles installed
are the culprit. If you have done in-place upgrade from older versions
then their might be unwanted SP/CFP bundles. You can safely uninstall
those bundles. We were on AEM 6.2 (CFP15) and we recently migrated to
AEM 6.5.5 and facing the similar issue and the culprit was some bundles
installed during CFP 10 on AEM 6.2. If you are not using, uninstall ACS...