Just to make clear: This is not advice on how to set up the celebratory meal and/or buffet
The original post on this subject can be found here.
While the link above will suffice, just remember these few tips.
If there is a ceremony (as opposed to a very private affair), the bris should be in a prominent place in the room
There should be good lighting, so the mohel can see what he is doing!
Every mohel needs a table to lay out his supplies. It should be larger than a TV table. A card table or most folding tables are adequate.
There either need to be one or two chairs available - for the Chair of Elijah (Kisei Eliyahu). If the chairs available are barstool height, there should be some kind of stepstool available for the Sandak to put his legs so he can easily hold the baby.
It is also very helpful for a private room to be designated or arranged (if in a venue outside of the home) for the mohel to examine the baby before hand and afterwards, particularly if he intends to check the bandage before leaving.