1. A method comprising: determining, by a processor of a wearable computing device and based on motion data generated by a motion sensor of the wearable computing device, one or more strokes; generating, by the processor and based on the motion data, a respective attribute vector for each respective stroke from the one or more strokes; classifying, by the processor and based on the respective attribute vector, each respective stroke from the one or more strokes into at least one category; determining, by the processor and based on a gesture library and the at least one category for each stroke from the one or more strokes, a gesture; and performing, by the wearable device and based on the gesture, an action.