When you find the cache machine insert your card in the slot indicated by the white arrows and open the cache. This will give you access to the log book. Use the waypoints to find the access route to ground zero.
Logging Etiquette: Geocache hiders sometimes go through a great deal of planning to place their caches. As a result, they'd like to hear your feedback on whether you liked or disliked any aspect of the hide, or if you feel that some cache maintenance is required. Single word, acronym, or emoticon logs may be easier when you have a lot of caches to log, but it doesn't tell the hider or other finders anything about your adventure (or lack thereof) in finding the cache. Please keep this in mind when entering your log.