Acclimatising your new corals is a vital process to ensure they survive and thrive in your system. People use many different methods but most of them are very similar, below is my preffered choice....

1. Unpack coral carefully from box and keep it in the polythene bag that it was shipped in.
2. Float the bag in your sump area or main tank for around 20 minutes, this will equalise the temperature of the water in the bag to that of the system it is going to be placed.
3. Open the bag or place coral with shipping water into another small container
4. Using a piece of airline or similar (see image) with an air control valve attatched, if one not available then just tie a knot in the airline, start a siphon from the main system and drip water slowly from there into the bag/container housing the new coral ( I use around one drip per two seconds ). Once the bag/container is near full then disregard some of the water and continue the process (never put any of the shipping water into your system). I persevere with this process for around 2 hours to ensure the new coral is fully aclimatised to the new water conditions.
5. Now it is time to remove the coral from bag/container and carefully place it in your tank somewhere near the bottom. Leave it there and raise it slowly over a period of days so as it can adjust to the different lighting on your tank.

This careful process is vital to your coral or any other livestock for that matter.