In the simplest terms yes you show up, trade an item if you want, and sign the log. But there is more to it than that. Its about the location and the trip getting there. Take some time a think about why the hider brought you there. Signing the log proves that you were actually there and found the cache. There is nothing that really says you have to sign it. There is actually a whole long post about that very subject. This game seems to be kind of wide open. People play how they want to. So have fun and see lots of cool things.