To sign good, take your outstretched hand with fingers together, and starting with your fingers on your chin, move your hand out and down in an arc. You may also have your non-dominant hand, palm facing up, to act as a support when your dominant hand leaves your chin, moving forward to rest on the non-dominant palm. However, this isn't necessary. When you sign good without the resting palm, it looks like the ASL sign for thank you.
The sign for good is a bit like you are blowing out a kiss, but your hand is a little lower down.
Use good with things that your baby enjoys, particularly food. When your baby is visually pleased by an experience, use the good sign. When you say emotional signs like good, use a rising inflection to help communicate the meaning to your baby.
Adjectives or descriptors are a great way to help babies express complex emotions. Knowing the concept of good also helps with self-esteem.