Cut the rhubarb into small pieces. Remove any strings that hang off while cutting.
Add Sugar
Add sugar and stir to coat. Let rhubarb sit until juices begin to emerge.
Stir
As juices emerge from the rhubarb, continue stirring. Cover and let sit for at least 8 hours.
Lots of juice
Remove from refrigerator and place everything, juice included into a pot. Bring to a boil until jam thickens.
Test jam
You can test the jam to see if it's done. Place a spoonful on a plate and allow to cool slightly. Run a spoon through the center. If the jam stays separated, it's done.