Making mulled wine is a very subjective thing, keep your personal tastes in mind before you begin. Do you like cinnamon, cloves, honey or star anise? You don't need to add any of the spices you don't care for.
Greeks and Romans spiced and heated their wines to keep warm in winter. I'm sure they merely did it to taste.
Begin with two bottles of dry red wine in a large saucepan.
Add one large whole thinly sliced orange or two small oranges, clementines or satsumas
Add the grated zest of an orange or lemon if you like tangy citrusy flavors
You can choose to add any fruits such as pitted cherries, pomegranite seeds, cranberries or sliced apples
Half a cup of brown sugar or honey
You can grate in a small amount of nutmeg to taste
Add two cinnamon sticks, four cloves and two star anise, choose only the ones you like.
(Keep aside several sticks of cinnamon to add to your glasses as a stirer)
Simmer the ingredients on low heat stirring occasionally for forty five minutes, never boil as it will cook off the alcohol.
You can add half a cup of brandy to the pot or a small glass of port to add richness at the end.
When the fruits have cooked to a softness turn off the heat.
At this point you can either sieve the mixture providing a smooth liquid and adding back a slice of orange and a fresh cinnamon stick to each cup, or you could serve it as is in heat proof glasses or mugs.
Good Luck!