Next, clean the water intake with a damp paper towel. This could possibly be the most challenging part to clean on coffee makers. Some of them are very slim and it can be very hard to get your hand into with a wet paper towel. If that's the case, you can use a spatula or something with a thin handle to move the paper town around, thus cleaning it.

A soft nylon bristle bottle brush can also be useful. A toilet bowl brush will be too big.

Internal components can't be reached by hand of course. A suggested course of action is to run a 50/50 white vinegar & water mixture through your coffee maker. This will remove the scale and impurities left inside the machine over time. After running the vinegar through, run a couple batches with clean water to flush the taste of vinegar out.