wtf is wrong with you yanks? i dread to think what macaroni cheese tastes like over there.
here in the UK:
boil pasta (obviously)
while pasta is boiling, make a béchamel sauce. you evidently don't know how to do this so:
1. melt generous knob of butter in a pan (large table spoon for 1 person)
2. slowly mix flour into melted butter over a low heat, making sure the consistent is smooth. should be about 2 or 3 tablespoons worth of flour, but keep going until it almost forms a 'dough' consistency. this is called a roux.
3. take off the heat and SLOWLY add milk. once you have a thick, smooth liquid, return to the heat. keep stirring and adding milk when the sauce becomes thick. you should be able to add several cups of milk.
4. add a teaspoon of mustard! yum.
5. add grated cheese (or several cheeses) to the warm sauce, to taste.
mix the sauce and pasta in an oven dish, cover with plenty more grated cheese. bake. nom.
add bacon or ham to the pasta, or sliced tomatoes on top, if you like.