if you want roasted garlic oil, you can put whole cloves of garlic in olive oil, make sure the garlic is covered. put in a 300F oven for about 30 minutes, keep checking the garlic should be golden brown,
remove from oven and a pinch of salt, and allow to cool. Strain out garlic and save for mashed potatoes, Your oil is now garlic oil.
If you want you can puree the oil with the garlic, It won't have the nice appearance of clear oil anymore, but if its just for flavor that won't matter. If you want to spruce up the look of it, you can always add fresh herbs and make a pistou.
If you want a raw garlic oil, just throw some olive oil in a blender, and puree up some garlic, let sit overnight and strain the next day.
Use within three days, as garlic can cause botulism under the conditions that oil provides.
All it needs is a little salt.... pepper.... mustard, catchup, sauce, flavour. -- Trapper