How to best position WiFi access point and its aerials?

What's the preferable way to position a WiFi access point and its aerials for best WiFi functioning?

Do I hang it under a ceiling or at some other height? Do I mount it parallel to the wall or do I incline it? If the access point has rotatable aerials - how do I position them?

Solution 1:

If all computers are not getting good reception, you can download this free program (inSSIDer). This will show you signals from all WiFi in your area and what channel they are on. You can ensure that you have different channels 1 - 11 you will not always be able to as they can overlap.

You can also place the base station centrally on an upper floor, or atop furniture, because radio waves spread best laterally and down. Reception will be better if the signal does not have to travel at steep angles and if it doesn't have to go through thick walls, mirrors, fish tanks or anything metal. inSSIDer is no longer free(it cost about $20)
Another 8 hints from this article on lifehacker.com and more detailed information on this Wikipedia page.
Added free wifi options:
1.From 'Software recommendations' a stackexchange website (search for wifi)
2.From nirsoft home of many good free programs.
3.acrylic-wifi-free
4.netspot
I like nirsoft but that is just me, netspot, acrylic, and the 8 hints provide a same style and an at least as good as inSSIDer display and service.