https://en.wikipedia.org/wiki/Emile%2C_or_On_Education
Rousseau recommends: Night games, obstacle courses, Natural Method (Parkour), but in short the idea is to let the child be self-directing in their activities. In Rousseau's words, "to gain time by losing it." ie. don't try to direct their activities. Do what is necessary and dutiful in your own regard and teach through example and necessity; never through imposition unless absolutely necessary.