Kay, I have a Panasonic Lumix 10.1MP Digital Camera (DMCFZ28K) and I need to know how to change shutter speed?

I need to get my shutter speed down to about 14 seconds, I%26#039;m trying to do light graffiti.|||you might be able to find it%26#039;s user manual online http://shopping.yahoo.com/search;_ylc=X3鈥?/a>