Night diving is special because even a familiar site looks different at night. At night, you see only the area of the dive site that is lit by your light. This forces you to slow down and concentrate on that one area. Here are some tips to have a fun and safe night dive:
Stay close and shallow.
Get the right gear. You'll need a primary dive light and a backup light. Never shine your light directly into another diver's eyes--you can ruin his night vision.
Go easy on the light. You'll find smaller primary dive lights do just as well, particularly in clear water.
Before you make your first night dive on a site, you should dive it during the day. This allows you to learn the layout of the site and get comfortable with it.
Most important, relax and enjoy the dive. It's natural to be a little anxious before stepping in the dark void of an unlit ocean or lake, but it's also exciting. When you overcome your anxieties about night diving, you get another eight hours of each precious dive day to explore and create new and lasting dive memories.