We followed two girls around the hallways, and we listened to them for about 3 minutes until they turned a corner where it might be really obvious that we were following them. We also followed a group of 2 guys and 1 girl. It was weird to write down everything they were saying, but I listen to peoples conversations all the time so it wasn't that weird. One thing we noticed was the manner in which they spoke. The two girls spoke like they were good friends, being very honest and agreeing with each others opinions. The other group didn't seem to be very good friends, it was a very one sided conversation with the girl trying to impress the 2 guys. This could be applied to your writing by knowing who your characters friends are, your characters conversation would be more personal with their friends than a group of people they barely know. Peoples character can be revealed through conversation by the tone of their voice, and also through exaggerations they use. If the conversation is very one-sided, that person may just be talking for the sake of talking. When more than two people join a conversation, it becomes louder as everyone is trying to get there ideas heard, or it becomes a conversation between 2 people with 1 person listening. It's surprising to hear how many conversations are just pointless. I don't think any of the people in these conversations are benefitting from talking about how annoying their parents are. Written conversations usually have a point, and are there for a reason. They are often very descriptive in describing body language and emotions in their voice. Spoken conversations tend to be very pointless, and don't contain much meaning. You wouldn't put a spoken conversation into a story, as it doesn't benefit to the plot in any way.