Usually you don't have to create a config file yourself. As distributed, the lircd.conf.d contains a file devinput.lircd.dist. This can be used by renaming it to devinput.lircd.conf. If required, the config file can be re-generated using lirc-make-devinput.
This driver uses /dev/input/event0 as its input device per default. You should provide the correct device as --device parameter on the lircd and irrecord command line.
The driver supports enumerating the available devices using mode2 --driver devinput --list-devices.
Sometimes the input device mapping changes between system reboots. In that case it is possible to specify the correct input device by its name or physical location by preceding the desired value with name= or phys=. See the Configuration Guide.
In simple setups, where there is just one device available (i. e., there is just a single /sys/class/rc/rc0 directory) the device can be given as auto.
The devices under /dev/input are often writable for some group. On Fedora, current user can be given access to these devices using usermod -aG input $USER, which adds the input group to the grouplist of current user. Other distros have similar steps.