I'm just gonna' ramble a bit about my experiences reading coals.
First laughter and being relaxed are always good things. I used to get very intense hours before ceremony and my teachers would tell me not to start the ceremony before the ceremony. In other words there's a time for intensity and pre-ceremony isn't it. Although, there's a balance. Those that choose to sit by the fire or tend the fire, stay in a casual state of prayer. Talking and laughing are perfectly fine, as long as the largest focus in our thinking, actions and words is the sacred fire. What it's showing us, what's changing, such as the direction of the flames, or any oddities that might occur with the fire. Our hearts and minds open up to the essence of it, the beingness of it, and the spirit beings that come to it. It's also fine to go inside and not sit by the fire. Actually, everything is perfectly fine. There really are no rules. Our experience should flow with the energies surrounding it.
Also, before the coals are ready, you can put prayers into the fire with objects such as tobacco ties, or just plain tobacco, written petitions, prayer flags, and offerings of any sort. I think in Judaism they offer bread to the fire. Whatever comes to you is fine. You cannot hinder the power that belongs to fire with your offerings.
So, the fire has died down and the coals are glowing. We start with a formal invocation, such as a song or prayer or statement of intent. Then everyone becomes quiet, so as not to interrupt anyone who is getting a message or viewing images in the coals. We say out loud what we see, even if we don't understand the image. The image will be significant for someone in the ceremony, even if the reader doesn't understand it. We keep in mind that reading the coals is a tribal, family, clan ceremony. The images are meant for us and are generally not about the outside world. This is a very intimate ceremony and was used originally for the survival of the tribe, clan, or family. What will the weather be, where will the buffalo be, what obstacles can we avoid. Today, we are an extended family with few of us genetically related, but we still need to know what's coming, how we can make our lives better and avoid any obstacles that are not conducive to our life experience. (Although, messages from the fire are not always about future events, they can be about what is necessary now.)
It's really important that everyone understand that we can all do this. Reading the coals isn't for just for seers or specially gifted people. This is a family ceremony and the key is not to censor anything you see. Trust it and say it. Even if it seems crazy or silly. It will be significant for someone.