Soak the flax seeds. Add the flax seeds and water into a medium bowl and stir. Let the seeds soak for at least 1 hour. You can let the flax seeds soak for up to 24 hours - in that case, soak the flax seeds in the refrigerator. However, the longer the soak, the thicker the mixture will get. A short soak will allow you to spread the mixture whereas a longer soak will require rolling. If you let the mixture rest for too long (and it begins to get dry), you can add a little bit more water to make it spreadable again.
Preheat the oven. Arrange a rack in the middle of the oven. Heat the oven to 300°F/149°C.
Spread/roll out the mixture. Transfer the mixture onto a parchment paper-lined baking sheet and spread/roll it into an even, thin layer. The thickness of the crackers is up to you. Ideally you would have about two layers of flax seeds. Too thin and the crackers will be very fragile, too thick and they will not crisp up properly.
Score the mixture. Using the tip of a knife, score the mixture into any shapes you like. I cut the Flackers into squares, but it's up to you. If you're going for a more rustic look, skip the scoring.
Bake. Bake the crackers until crispy and golden brown, about 40 minutes, The time will depend on the thickness of crackers. If the crackers aren't fully dry after about 40 minutes of baking, turn the oven off and leave the crackers in the oven as it cools. The oven will serve as a dehydrator, drawing any extra moisture out of the cracker.
Cool. Transfer the baked "cracker" onto a cooling rack, so air can circulate and no condensation takes hold. Once cool, break the cracker along the scored lines.
Store. Leftover chia seed crackers keep well in an airtight container in a cool, dry, and dark place for up to 1 week (or in the refrigerator for up to 1 month). For longer term storage, freeze in an airtight container for up to 3 months.