Register application to get API Key and Shared Secret

Go to http://www.flickr.com/services/api/keys/ and click on either of the blue buttons: 'Apply for a Non-Commercial Key' or 'Apply for a Commercial Key'

Fill in the form and click 'Submit Application'. Flickr will give you a new API Key that looks something like:

   0123456789abcdef0123456789abcdef

and Secret which looks something like:

   fedcba9876543210

You now need to change the key to be of type mobile with 'Edit key details' since no callback URL is usually appropriate for a command-line application or library. Set the permissions to 'read', 'write' or 'delete' as appropriate.

The result will be a new key with an 'Auth mode Mobile' and an authentication URL that looks like:

   Mobile (http://www.flickr.com/auth-11111111111111111 Read)