If you're coming to the full moon party taxi/truck, you will be stopped by police and asked to open bags and somewhat searched. So if you're planning to bring anything that you don't want the police to see, leave it back at your bungalow.
As for at the party itself, don't bring any valuables and watch out for pick pockets. There are a countless amount of people just waiting to take advantage of drunk people and their lack of judgement. Just bring cash to the party and leave any valuables with the bungalow safe - if you can trust them!
Make sure you don't leave any valueables in your room on the night of the full moon either! I've had friends get their stuff stolen on the night of the party because robbers know that no one will be at the resort and take advantage. Again, leave valuables in a safe with the resort or bungalow.
Have a blast!!
WARNING! WARNING! WARNING!
If you drink Sang Som, you may not be able to stop!
I have personally had an experience with this alcoholic beverage and it caused me to have a wild, exciting night.
This drink may cause memory loss!
1) take care of your belongings. Keep them in the safe of the bungalow if they have them. 2) Be very careful swimming on the west coast, as the coral is redicuously sharp and can easily slice open feet, arms, hands and anything else. 3) if sleeping near Sri Thanu, know in advance that it IS the main fishing port of Koh Phangan, and that boats tend to leave early in the morning. Like 6am or earlier early. Also know that all these boats have some sort of amplifier on their exhaust. They believe it chases the evil spirits away.
It's best not to rent a bike at this island. The roads are very bad.
Many tourists have bike accidents here, because they lost control of their bike. Their wounds are called: the bike scarifications / souvenirs.
Also when renting a bike: watch out for the insurance. When you don't talk about it and pay for it before renting a bike you will be sure of having to pay for it all when the bike is ruined or stolen.
I didn't go the Black moon party down at Hat RIn but have friends who have. Beware of what you take, eat and drink. If someone offers you something and you don't know them, don't take it. just common sense really. There's lots of drugs there and on the island but it's easy enough to avoid if you want. Jellyfish aren't as easy to avoid but just stay away from them if you see them. They aren't fun to be stung by to say the least. Don't worry about Sharks, you'll be lucky if you see one really. I'd be more afraid of just walking down one of the roads on Phangan than sharks or jellyfish or that stuff.
If you are heading to north-east part (Paanburi etc.)of Phangan, you need a 4 wheel drive jeep or powerful motorbike. The road there is absolutely worst i ever have seen. And i have seen a lot.
There are holes with depth of half meter, road is narrow and the uphills and downhills are unbelievable.
Do not bring your valuables to the party. Thousands people are there, you'll never catch the thief. Full Moon Party is the big day for robberies, because nobody is staying in the bunglow. Most bunglows provide lockers for you, don't leave valuables in room.
A meditation-retreat means getting up at 4 in the morning, doing sitting meditation most of the day. And beware: it could change your life!