And finally, you will encounter some skulls that need to be mounted at an angle to look right ... i.e. some semblance of natural. The horns should be mounted nearly vertical to the wall to show them best. A buffalo skull mounted flat against the wall may show the bosses but not much else. The drop, curl, and spread show much better if skull nose is tipped out about 35 degrees. Waterbuck need to be tipped at an even greater angle. Mounted flat to the wall, those horns stick straight out in the room. Others like impala, blue wildebeest, gemsbuck, and springbuck are fine mounted against the wall. Kudu, blesbuck, and hartbeest should be tipped a bit.
If you have a table saw, I can help you through making the tipping supports. A radial arm saw is ideal or a slider chop saw. It's not rocket science. Nobody showed me but I'm certainly willing to pass on what's worked for our business.
Lastly, though some may think the "pure" European look of half sawn skull on a fancy baroque plaque is the only way to go, keep a few things in mind. Cutting a fragile skull cleanly requires the right equipment. And you have only one presentation option: flat against the wall. As mentioned above, many animals don't show well that way. Finally, plaques are dust catchers. The darker the wood, the more the dust shows. Cleaning them without removing the horns can be laborious.