Of course I’m going to suggest that you buy fresher beans, fresh is more important than varietal, in my opinion. I’ll take just about anything fresh over a six-month-old, formerly exquisite Cup of Excellence, any day. But beyond fresh beans, there’s something else you can do to make better coffee – grind them yourself at the time of use. Fresh coffee has a short shelf life (think weeks, not months), and buying it pre-ground means it will be stale sooner.
Much has been written about the science of coffee grinding, such as this example. There is not much point in me repeating the good work that’s been done, my motivation is to get you to grind it yourself!
There is a lot of debate about the “best” grinder. While the high end can run hundreds, thousands of dollars, or even more (and are not likely to be usable in the home), if you can spend $100, you can get a really nice burr grinder for home (we recommend the Baratza Maestro). But if that amount is more than you’re willing to spend, just twenty or thirty bucks will buy you a blade grinder (the kind that have a flat metal blade that spins like a lawn mower) that’s better than nothing, and you can pick them up just about anywhere kitchen appliances are sold.