How do I know if my baby and I have formed a good bond?

A WARM FUZZY...... A warm embrace, smile and eye contact starts that first moment that you see your baby and it continues till that baby brings his or her babies into your life.At times they will make you sad, mad even exasperated, but that warm fuzzy feeling that you get when your child looks at you , smiles or simply says mom or dad...That is when you know you have bonded.
For a small baby... ...That means good eye contact and mirroring your expressions and moods. For an ambulatory child, "secure attachment" means [s]he is not distressed to be separated from you, and is very happy (not angry) to come back.
Baby responds by age. A newborn simply is calmed by your comforting hold and loving words. (though if a baby is sick, hungry, or colicky, it does not mean you aren't bonding if they keep crying!) after about 2 months a baby will smile responding to you. At about 4 months they should laugh and begin to coo back. Older babies will cry when you leave and be calmed upon your return.