How long is a good time to tan while using Hawaiian tropic dark tanning lotion?

Work yourself up in time. Try 10 minutes one day. If you don't notice any pinkness after 24 hours, bump it up to 15 minutes the next. Go up in 5 minute intervals. As soon as you see some pinkness, drop a few minutes and stay at that time for a few tanning sessions. It takes 24 hours for your skin to completely react to the sun, though. So, in the beginning try not to tan too often until you know how your skin will react. Burning is very bad for the skin.