Most explanations I’ve found are spotty. Here it is all summed up.

Config Change Notifications and Logging

Turn on config change notifications and logging

!- Enter archive config mode
archive
!- Enter log config mode
log config
!- Enable logging
logging enable
!- Max the entries at 1000
logging size 1000
!- Hide any keys or passwords from showing in the log
hidekeys
!- Send syslog messages if you'd like
notify syslog

View it!

Router# show archive log config all
idx sess user@line Logged command
1 1 admin@console logging enable
2 1 admin@console logging size 1000

Config Auto-Backup

!- (optional) Make a folder for your configs
do mkdir flash:/archive-configs
!- Enter archive config mode
archive
 !- Choose a path for your configs (can also be any ftp, http, https, rcp, scp, or tftp server)
 path flash:/archive-configs/rollback-
 !- Create a backup whenever you manually save the config
 write-memory 
 !- Retain a maximum of 14 backups
 maximum 14
 !- Save the config every "x" amount of minutes
 time-period 1440