How to teach colors to kids?

How can my friend get her 3 y/o daughter to learn her colors

play count the blue cars for fun or like slugbug. dress in one color a day and do this for a couple of months. like tuesdays is green day so you wear green and wednesdays are orange days. It is kind of fun for both of you.

Play games with her like find the red crayon (only have a couple available), or point to several t-shirts one by one when the girl is about to be dressed and say (with pointing), 'What shirt will you wear today? The BLUE shirt ... the RED shirt ... or the YELLOW shirt?' If she responds with a choice, lots of praise and use that shirt. If there is no response then after a few seconds, the Mom should cheerfully say 'Let's pick the RED shirt (or whatever)'
The idea is to make it playful and fun.

Best wishes to your friend and Good Luck !!

When I was little, we used the rainbow song:

'Red and yellow and pink and green,
Purple and orange and blue,
I can sing a rainbow, sing a rainbow
Sing a rainbow too'

We would draw a rainbow while we sang it, using the right colours to draw the rainbow.

One thing I will advise you on is, don't push your child to learn them if she's not interested. Working in pre schools, there are some children who are interested in shapes (one child I worked with could name and identify most shapes before she turned 3), some interested in colours, names, animals, and some aren't interested in any of those. Let her go at her own pace, and don't push her too hard.

this is how I taught my little sister her colours.
find a room or garden that has lots of different colours.
then say 'find something that is blue' and she has to run and touch something blue.
give lots of praise and start again with another colour.
hope it helps