Pairing is when two attend an otherwise private lesson at the same time. This costs slightly less but usually dramatically decreases the rate of learning for each person. I've discovered that two is still a class and requires the same approach to teaching it as for a larger class. A solo private lesson by comparison progresses not just twice as fast, but usually five to ten times faster. For this reason I strongly prefer to accept private students over paired (even though financially it is significantly worse for me).
How do I get a pair?
You find your pair and have to arrange it. I do not pair anyone.
I do, however, reserve the right to refuse a suggested pairing at any time during or before a block of lessons. A bad pairing can absolutely destroy the learning of one or both. At best, a good pairing provides some social opportunity and motivation. Pairing always slows down the learning, however.