An excerpt from Tech Republic here:
Takeaway: When you set up a wireless access point, certain basic practices can help you avoid problems. Brien Posey offers his advice for a successful deployment.
Wireless hardware manufacturers have made the process of setting up access points fairly painless, but there are still some best practices you should follow. Here are a few pointers for anyone who is about to deploy a new wireless access point.
1: Avoid placing access points near structural metal
When setting up a new wireless access point, you should install it in a location that will be unlikely to cause radio interference. I once had someone contact me because their wireless network was not working correctly. When I asked them to show me the access point, they led me into the warehouse where the access point sat on top of a steel beam just beneath a metal roof. The surrounding metal was interfering with the signal. Moving the access point took care of the problem. Since that time, I have always advised clients not to place access points in close proximity to structural metal.
2: Use Power over Ethernet when necessary
Many organizations like to place wireless access points on or near the ceiling in an effort to help wireless clients achieve the best possible range. But it can be difficult to get power to the access point. Rather than rely on extension cords (as I have occasionally seen done), consider using Power over Ethernet (PoE). PoE provides the access point with power over unused wires within an Ethernet cable. Special PoE modules at each end of the cable ensure that networking hardware is not exposed to the electricity the cable is carrying.
3: Reset the access point password immediately
The first thing you should do when setting up any new wireless access point is reset the access point’s internal password. Otherwise, the access point’s configuration interface will be accessible to anyone who knows how to look up the default password on the Internet.
See the complete list Here.