If you want to let people know what you do for a living without presenting yourself in a cocky manner, then you must read more.
Setting is Key
Be conscious of where you are. Some social situations lend themselves better to casual conversation than others. For obvious reasons, you may want to think twice about handing out your business card at a worker's strike. However, a pool party, a dinner party, a book club, or any other relaxed atmosphere may prove your best option for updating members of your circle on what you have been doing lately.
Timing is Key
Keep an ear out for key words and phrases like “I've been looking for a way to supplement my income” or “I live hand-to-mouth as is” or “holiday shopping season is upon us”. Anything that may open up the door for you to present an option for bringing in a second income stream. If you are wildly successful at what you do, you could even help someone else learn the steps to being just as successful.
Phrasing is Key
“I work at home” sounds like you are as laid off as a quarter of the country. Try pointing out the important aspects of what you do in your home-based business. Do you use the internet to help others fulfill research requests? Do you match people with a business that suits their skill and commitment level? Do you write business communications for local commerce? Do you build and host web sites? Something interested you in doing what you do now, so let others feel that excitement, too.