The chakra sound you meditate to OM. It sounds like OOOHHHMMMM (Long O). To use your energy flow to help place the tips of your thumbs together with your pointer finger tips bent down. This will look like a heart. Then extend your middle fingers up to form a point. Leave your ring and pinky fingers pointing down with the tops touching. Hold your hands with the thumbs pointing towards you in a comfortable spot between your heart and navel chakra.
As you open your third eye up you will perhaps feel pressure in the head or have pain in the area of you third eye. This is because your body and mind need to get readjusted to the third eye being open. If this happens take a break and come back to opening the third eye at a later time. Your third eye will take sometime to open 100%. The other thing that you need to practice is closing your third eye as well. This is a defensive move to help protect your self during times when having your third eye open can be harmful.