1. Use a cocktail shaker:
I had one sitting unused in the closet, a birthday present that came with four cocktail glasses. Instead of using it, I would pour two or three kinds of expensive booze on ice and wonder why the drink didn’t taste better than the sum of its parts.
You never see a good bartender doing this. I don’t want to get into the merits of shaking with ice versus stirring: personally I like cocktails shaken because I like them a little frothy. You can stir if you want, especially if you don’t have a shaker yet. But the point is, mix the cocktail in one vessel, and serve it in another.
Now I feel my previous efforts were like eating directly from the frying pan.
Ten Easy Tips to Make Delicious Cocktails (a slideshow)