My daughter decided before her baby was even born that she was going to teach the baby sign language. I was skeptical and uncertain why you would want to sign to your baby. Would the little one depend on signing and not learn to talk? My niece did some limited signing with her little one and felt that it was a deterrent for him in beginning to talk (let me tell you - he is now three and he definitely talks!). So, when my granddaughter was about five to six-months-old my daughter started signing to her. She initially used three to four signs: drink, milk, more, and bath. As she got older, more signs were introduced: water, ball, duck, please, eat, and noises. This went on for months and months with seemingly no results.
Once baby girl hit her first birthday, it all started to sink in! She started with the sign for more. More fruit, more milk and then more tickle!! We knew she understood exactly what more was when she wanted more tickles. It's one thing to want more food, but more tickles seemed to prove that she knew what more actually was.