Here's an eggnog recipe. I prefer putting some Bailey's Irish Cream (or similar) in instead of the rum but you can use anything

Ingredients

first measurement is for 4 servings, the second is for 8 servings and the third is for 12 servings

Fresh eggs (seperated into yolks/whites)
4
8
12

Sugar (divided into 2 equal parts)
1/2 cup (1/4c, 1/4c)
1 cup (1/2c, 1/2c)
1 1/2 cups (3/4c, 3/4c)

White Rum
1/2 cup
1 cup
1 1/2 cups

Milk (Whole or 2%)
1 1/2 cups
3 cups
4 1/2 cups

Whiskey
1 1/2 cups
3 cups
4 1/2 cups

Heavy/Whipping Cream (divided into 2 equal parts)
1 cup (1/2c, 1/2c)
2 cups (1c, 1c)
3 cups (1 1/2c, 1 1/2c)

Ground Nutmeg (strongly recommended)
Enough to sprinkle on servings.

Eggnog Recipe Instructions
You are doing things gently and slowly to preserve the eggnog's fluffiness. A good whisk for the stirring and a high speed mixer for the egg-whites and cream helps this process immensely.
Separate eggs into yolks and whites in separate bowls. I put the whites into the mixer and the yolks into another bowl.
Beat egg-yolks with 1/2 of sugar, set aside.
Beat egg-whites until stiff, then mix in other 1/2 of sugar.
Poor the yolks into the whites and mix together slowly.
Stir in white rum slowly
Stir in milk slowly Stir in whiskey slowly
Stir in 1/2 of cream slowly
Whip rest (1/2) of cream and fold in carefully. .
Serve at room temperature by ladling the eggnog into cups and sprinkle nutmeg on the top. Try to get some of the foam and some of the liquid (if not fully mixed) in each cup.