More advanced users may want to migrate to the JOSM editor at some point for improved editing efficiency or specialized needs.
JOSM Training resources
learnOSM.org has many JOSM detailed editing resources in many languages.
Mapbox launched Mapping with OpenStreetMap Mapping guides. The guides offer comprehensive training with JOSM including how to become a power mapper and validating OpenStreetMap.
Additional JOSM tips:
Activate Remote Control. Make sure Remote Control is turned on (this allows the HOT Task Manager to send data directly to your JOSM session): go to Edit⇨Preferences; on the left click on the Remote Control icon (third from bottom), put a check in the box “Enable remote control”, click OK.