How to identify unused databases on my sql server

I am looking for the best practises or analysis someone would have followed to identify the unused or inactive databases on my sql server.

I went through many articles, which says like possibly to go for user connections and activating traces to find the DB usage, but implementing those created more confusion.

Kindly help me in understanding if there is a better and safer wayi can take my DB's offline once identified.

Thanks Kapil