A net is an on-air meeting. In a directed net, one station, the net control station (NCS), runs it: calls it to order, decides who speaks next and keeps order. Without one, a busy channel degrades into everybody talking at once. The NCS is the traffic director, not the boss: it does not choose the net's schedule or check licenses.
Stations talk through net control's direction. Exception: an emergency report.
Stations transmit only when directed. The one exception is a station with emergency traffic, which may break in and say so.
Running the session
A typical order, not a rule: your net's own procedure comes first.
The order above is typical. A few points make it work:
Open clearly. Say what the net is, its purpose and the frequency, and give your own call sign. Identify as Part 97 requires: at least every 10 minutes and at the end of the contact.
Ask for emergency and priority traffic first, before routine check-ins, so urgent items are not stuck behind a long list.
Take check-ins in an orderly way. Ask for calls in groups, such as by call sign suffix, or by a list the net uses. Repeat each call so everyone hears it, and write it down.
Keep your own transmissions short. Every second of NCS talk is a second a station cannot get through.
Traffic and relays
Traffic means the formal messages the net exchanges. The NCS pairs up stations: "K1ABC, you have a message for the shelter; go to W2DEF and pass it." Messages follow the format in Radiograms and message handling.
When one station cannot hear another, the NCS can ask a third to relay. Where reach is the limit, big nets use an alternate NCS or a relay station and, for large incidents, multiple linked nets.
Joining a net
Listen first to learn the format. Check in when called, using the style that net asks for (often just a call sign, phonetically). Then wait for direction. If you have something urgent, say so and be ready to give it briefly.