Dialling in means finding the grind setting that makes a coffee taste its best on your grinder and machine. It's quick once you only change one thing at a time.
1. Fix the dose
Pick a dose that suits your basket (often 18 g for a double) and weigh it every time. Changing the dose changes everything else, so leave it alone while you dial in.
2. Start from a typical setting
Start from your grinder's usual espresso range (see the grind size chart), then aim for a ratio of about 1:2, so 18 g in and 36 g out.
3. Use the grind for time
A good starting target is 25 to 30 seconds for that 1:2 shot. Too fast? Grind finer. Too slow or choking? Grind coarser. Move one or two steps at a time.
4. Use the ratio for taste
Once the time is in range, taste it. If it's sour or thin, let the shot run longer (1:2.2 to 1:2.5). If it's bitter or harsh, stop it shorter (1:1.8 to 1:2). Light roasts usually like longer ratios and hotter water, and dark roasts like shorter ratios and cooler water.
5. Write it down
When it tastes right, record the grind, dose, yield and time. Fresh bags of the same coffee drift as they age, so expect to nudge the grind a step finer over a couple of weeks.
Find your grinder's typical settings in the grind size chart.
Notchbook is a free app that remembers the grind setting that worked for each coffee, grinder, brew method and filter paper, and keeps a journal of every brew. Get it free on Google Play. The iPhone app is coming soon. More about Notchbook.