I will add, the fasting from food and water is the easy part. The more important fast is fasting from everything that is bad -- cursing, backbiting, lying, etc -- and from your own desires. All these things are things you shouldn't do anyway, but this is a time to refresh commitment to not doing those things.
As the Quran says: "Oh, you who believe! Fasting is prescribed to you as it was prescribed to those before you, that you may learn piety and righteousness" [Quran 2:183]
As the Quran says: "Oh, you who believe! Fasting is prescribed to you as it was prescribed to those before you, that you may learn piety and righteousness" [Quran 2:183]