Form a playgroup with other parents and babies from your neighborhood, work or place of worship. It doesn't have to be formal, but you should establish a regular meeting schedule. You also should consider a consistent location for your playtimes, or establish a process by which you notify participants of the next meeting's location. The time spent with other babies will allow your little one time to work on her people skills and your time with other parents can provide you a sounding board against which to discuss any concerns you might have.
According to the American Academy of Pediatrics, your baby may be able to crawl as early as six months. Use gates on stairways and close doors to keep your baby out of rooms where she might get hurt. Get a head start before your baby starts crawling.