Before you blame the press or the beans, look at your grind. When I help people sort out weak coffee, nine times out of ten the grind is the culprit. Pre-ground coffee labeled "coarse" is often too coarse for a French press—it looks like breadcrumbs and lets water race through. That means the water barely touches the coffee, so you get a pale, thin cup.

If you're grinding at home before you leave, aim for something between table salt and sugar—not powdery fine, but definitely not chunky. If you're stuck with pre-ground, try steeping longer and using a bit more coffee. But honestly, a small hand grinder is worth the luggage space if you travel often. You can get one for less than the cost of a few café lattes.

Once the grind looks right, check your ratio. The standard is 1:15—one gram of coffee for every 15 ml of water. That works out to about 30 grams for a 450 ml press. If you're not weighing, use two tablespoons per cup, but weights are more reliable. I know it feels fussy, but a cheap scale transforms your consistency.