What to do or what to drink for leg cramps?

Walk, minerals: Assume the following: no serious nerve damage or arterial obstruction to the limb, then try calcium-magnesium-potassium tablets which can be highly effective (be sure to use lots of fluids when taking). Sometimes you may have to get up & walk it out, massage it out, or passively exercise the cramped muscles. Warmth may help--avoid overheating the limb.

Leg cramps: Tonic water. It has quinine which helps with cramps.