a) Talk about what you’re doing: A running commentary is all that’s needed. Your baby will learn the names of objects and will react to your excitement about people, places and events.
b) Address your baby by name: Studies indicate that while babies may not recognize their names until after the first year, they will associate the sound with exciting things that follow, and have a reaction. Research by Marianella Casanola, PhD, of Cornell University also shows that during the first two years of life, infants are learning about language long before they speak it. 
c) Ask questions: Your baby will pick up your patterns of speech and learn that the uplift at the end of a sentence invites a response.
d) Sing: Put on your favorite music and rock out. Give your baby a variety of styles: Whoop it up to opera, shout it out with The Beatles, get dramatic to classical and stomp around to country. While science is still exploring whether listening to music actually makes a baby smarter, new research has found that the act of playing an instrument may be even more beneficial for brain development than we thought.  And no better way to encourage that than a good Katy Perry tune.
e) Touch: Again, holding, massaging and hugging your baby is instinctive, but research shows that touch also enhances learning. So tickle and tumble away. 
f) Dance: A great way to combine both music and touch is dancing. With your baby in your arms, sway and bounce around the room – it’s a good workout for you as well. Try all kinds of music; one of my family’s favorites was Michael Nyman’s haunting soundtrack to The Piano.
g) Get down and play: You know how much fun it is to play peek-a-boo with a baby; facial games from as early as two weeks old also get your baby focused and learning: Stick out your tongue, blow raspberries and google your eyes – you will start triggering those trillions of brain cells to make connections .
As your baby grows, play with her on the floor with rattles, balls, animals and other toys she can grab. One of the most exciting milestones was when my girls started reaching out for a toy; make sure you have simple ones that they can hold easily. At six to nine months old, your baby will love playing scoop and pour in the bathtub with a plastic cup, bang the drum with the kitchen pots, and stack and destroy on the beach. You don’t need to buy a lot of toys – you are your baby’s best plaything!
h) Read: Yes, you know that it’s never too early to read to your baby, and Goodnight Moon is adorable – also check out Runaway Bunny and my favorite, The Kissing Hand by Audrey Penn  – but even reading your favorite book or magazine aloud can be fun for your baby if you spark up the words for her.
i) Feed her brain: Make sure your baby is getting the proper nutrition daily; research does show that breastfeeding is best when it comes to baby’s cognitive growth, but you also can choose formulas that contain the omega-3 fatty acid DHA to help support brain and eye development.Bottom line: Engagement and communication are the keys to boosting your baby’s smarts, and, as a big bonus: It’s all FUN.