Tips for using Nikon D5000?

Going to take pictures of friends baby shower tomorrow just for fun and caused they asked me to. Just bought a Nikon D5000 but have just been sticking with auto setting. I don't know a whole lot. Does anybody have some tips like what time of the day has the best light and what settings to use to get very clean crisp pictures of them as group etc

Read the manual and practice. Play with the settings and figure out what does what. That's what I do with any new camera. I have the Canon T3i, just got it a few months ago, and I'm still learning what each setting does but I love the camera and the different options for photo taking on it.