Crocheting is the process of creating fabric from a length of cord, yarn, or thread with a specific type of a hook known as the crochet hook. Starting With a Beginners Crochet Block
On the internet you'll find patterns and plans for that will assist you in making this type of baby blanket gift. You will generally start with a beginners crochet block; as it is the start of many other projects. The library is a great source of crochet baby blanket patterns also.
If you are working with specific colors, you can not guarantee that you will be able to color match exactly the yarn you have been using. The best advice here is to pick out a neutral color that will work for either a boy or a girl. If you can't learn from the Internet and feel that you need more of a one on one approach, check with your local craft store.
As you practice, you will learn more and more. Remember that perfection is not necessary.