I've always had a hard time remembering which aunt/uncle/cousin/niece/nephew is who, so I put
all the terms in a family chart, and now I'm passing it on for everyone else.
In the event that we don't have a word for it yet,
such as "the spouse of my brother", I left it blank, as oposed to describing the relationship. I didn't want to confuse any new people (or old).
I also put all of the males on the left, and females on the right, it helped keep things simple and organized while I worked on it. -My granny who does geneology helepd me with the charts.