When my DD was that age, after all I read in the zillion of books I bought, I thought talking/singing to her was the best! At this age, they just stare at you and watch you and take in all that you are doing to learn from you. Based on this, I didn't bother with all the toys and educational DVDs playing in the background or whatever - I just talked to her and sang to her all the time! I'd use exaggerated arms and facial expressions sometimes, but basically I found just giving her plenty of eye contact and verbal drivel, and she always seemed happy enough!!
(Be warned though: after spending the day verbalising what you are doing "here I am in the kitchen... getting out the margarine... oh look, Daddy has put the empty container back in the fridge..." you will find you will do it out in public and get some strange looks! Nevermind! You may well be too sleep deprived to care anyway... !!)