The secret about the Doton Avatar is that you two palms have to be in constant contact with the earth.Meaning you cannot use them for jutsus.You can use a clone for this jutsu naturally.Once you have made contact,you close both your eyes,start to mold earth chakra from your palms and rising into Doton Avatar at a certain point of the field.It is the same way as making an Earth shadow clone though both your hands must be in contact with the ground and both your eyes must be closed.And seeing through his eyes,you can picture how Gaara was able to see through his sand eye.Though you are not putting your hand on top of it because your hand must be on the ground.Now you try ^^