Heart shaped grip= Put your hand in front of you like you are making a stop signal with both hands.
Now bring your hands toward one another. until the index fingers and thumbs touch one another.
Nowe overlap the thumbs slightly. The shape that your hands make is a heart.
Now just place a DB in there over your head with the palms holding one of the heads of the DB and the shaft/handle between the heads goes through that heart shape. Now press away.
I hope that is clear. Dont know how else to put it.