To get you off and knitting, you will need 2 pairs of the correct size needles, a ball of machine-washable wool, measuring tape, and a small pair of scissors. You will also need a tapestry or yarn needle. These are large blunt-ended needles with a large eye used for stitching the back seam and finishing off the bottom edge. Knitting worsted wool is a good choice,
Michaels Craft stores and some dollar stores have everything you need to get started, and they usually have a good selection of colours at competitive prices.
Then use these Learn to Knit Websites to start keeping another young head warm. Here are some videos that might also be helpful.
If you are new to knitting, then start by using a single colour. Stripes are an easy jump from there, and when you are feeling a little more creative, start to use some of the patterns.
Get started with Knitting Worsted Wool.