The key is to stay close without getting too close. You want the microphone to be about 4″, or 100mm, away from your mouth.
Before the item starts, sit in a position that feels comfortable and natural to be having a conversation with your fellow panellists. Then gently position the mic about 4″, or 100mm, away from your mouth.
Try to avoid fiddling with it or adjusting it once the item has started. The tech volunteer will make sure that your volume levels are adjusted appropriately to match the rest of the panel. Trying to help out by shifting around once the item starts will make their job harder.
Talk naturally and clearly, so that what you say will be picked up for the stream/recording. The best technology in the world doesn’t help if you mumble or are inaudible.