My project today. These instructions were originally from UC Davis but links change over the years.
Dry only fresh, firm garlic cloves with no bruises. To prepare, separate and peel the cloves. Cut in half lengthwise. No additional pre-drying treatment is necessary. Dry at 140 degrees for 2 hours, then reduce heat to 130 degrees until completely dry or crisp. If desired, garlic salt may be made from dried garlic. Powder dried garlic by processing in a blender or food processor until fine. Add 4 parts salt to 1 part garlic powder and blend 1 to 2 seconds. If blended longer, the salt will become too fine and cake together in clumps.