Box the Gnat starts with a boy facing a girl. They reach forward with right hands, and walk forward raising their hands to make an arch. The boy turns right and the girl turns left as the girl goes under the arch and the boy walks around her. They each turn a total of 180 degrees, to end facing each other again.
Typically Box the Gnat will be followed by another call that starts with right hands, in which case they keep holding right hands, blending the two calls together. If not, they drop hands as necessary to prepare for the next call.