The main OC documentation on setting up an S3 external storage node shows the required fields. But setting up the S3 bucket, activating the right sub-services for making the S3 bucket compatible with OC is not obvious.
This post is a general call for links to relevant tutorials, or if doesn't exist and someone would like to make a step-by-step guide, it would definitely be a useful doc to have.
If I can figure it out, i'll post about it here.
References found so far: