How to choose the captain who wins the priority by drawing lots before the first game and the fifth game of volleyball competition?

When you say priority here, you mean priority. In the first and fifth innings, the referee will ask the captains of the two teams to choose the pros and cons of the coins he throws, and stipulate that heads or tails take precedence. The team with priority can choose which side to stand on or serve first. However, in modern volleyball, serving first is not dominant in the game, so choosing the venue has become the first choice.