Connecting to multiple buckets in Couchbase using Ruby requires setting up and configuring separate connections for each bucket. This can be achieved by creating a connection pool object that proxies methods to individual Couchbase::Bucket instances, allowing for thread-safe access to different buckets. The process involves specifying key prefixes and pool sizes, as well as writing custom code to handle operations on multiple buckets. While the Couchbase-Model gem in Ruby does not currently support connecting to multiple buckets, developers can use a connection pool object to achieve this functionality, enabling them to map attributes of a model to different buckets when reading and writing objects.