Hi Joleen Tan !
Reg. colors for babies , you are right - the first 3 months they perceive high contrast images pretty well..., the geometric patterns on high contrast white , black n red are most preferred ones.
By 4 -5 months, their sight jumps high and they do recognize your face from all others in the world.
I moved from contrast cards to regular flash cards by 5th month. You could pretty well catch them by seeing your kiddo's interest .
By 8-9 month they would pretty much be aware of all shades of gray ! In short, babies first one year babies is to experience rich vision
Below websites could help you to proceed with RB for ur kid :
1. First and best where I find the best flashcards are from Brillkids website
Below are my fav. blogs n sites from great moms
2.Shen-Li Lee I'm sharing your website here for reference as its one of my favorite
http://www.figur8.net/articles/right-brain-education/3.
http://littletigergrowingup.blogspot.com/2012/10/right-brain-home-practise-28-months.htmlHope it helps you !
happy learning
cheerymom