Actually, the most optimal way to do it is cream and sugar first, then coffee like the brits do with tea. This is so the poured coffee mixes and dissolves the sugar without having spend time stirring with those wussy plastic sticks. ALso, you are less likely to get too much coffee, that overflows after you put in the creamer and sugar. I've seen idiots get a full cup and then put the cream and sugar in, like you think it's not going to take up more room?
The best thing is espresso, 1 1/2 oz, straight shot with or without sugar, drink it in 20 seconds and out the door. Almost as much caffeine as a regular cup..