I, myself, have turned to this route since I am unable to work due to a disability and cannot bring any sort of income to my little family of 3. One day I decided I would take some pictures of some of the hats I had crocheted for my daughter and post them on my personal Facebook page and asked if any of my friends would be interested in having one custom made for a small amount of money. Much to my surprise, I did receive a couple of orders for hats. Luckily, it was just in time for Christmas since my husband and I were in such a bad situation financially (he works on commission and work dries up in the winter months) and didn't think we would be able to give our daughter anything to celebrate her first Christmas.
For others who are interested in doing the same thing, I've compiled a few tips to help you along in your journey.
I would suggest creating a Facebook page with this name of your crafty 'lil' business. Then tell all of your friends and ask them to like it and ask them to spread the word to your friends. Networking is key. Find other Facebook 'vendors' and ask them if they would be willing to advertise your Facebook page on yours. In my experience, I found it quite difficult to get people to like my Facebook page for my crocheted items. This may not be the case for everyone because remember it's who you know and how willing they are to help you get the word out.
Provided that you have a bunch of items you've already crocheted up, take some pictures of them with a nice background (lay a sheet down on a couch and snap away). Once that is complete upload them to Facebook albums which you should create by category such as hats, afghans, baby, etc.. Describe your item in the caption, asking price, and the cost of shipping (if you choose to expand beyond just your friends).
There are also many free shopping carts out there that you can integrate on to your Facebook page. No programming required! Two of my favorites are Payvment and Storenvy. I personally prefer Storenvy, but the choice is up to you.
Lastly, the big thing to keep in mind is your cost, your time, and prices. In all honesty, what I've discovered is that people (non-crafters) don't really care how long it takes you to crochet that hat or scarf. The bottom line is the cost of the item and the cost of shipping. Your time is basically not worth much unless you're a super fast crocheter and can make multiples every day. The only real advice I can give to you is to take advantage of sales on yarn and yarn that you can pick up cheaply at a thrift shop to increase your profit margin. Never sell something for less then what it cost you. Good luck!!