There are no surviving dance manuals describing the estampie as a dance. Illuminations and paintings from the period seem to indicate that the estampie involves fairly vigorous hopping.
The estampie musical form consists of a series of verses, perhaps of different lengths, and 2 endings ("open" and "closed") (perhaps also of different lengths), which alternate. So a typical layout would be:
Verse 1, Open Ending, Verse 1, Closed Ending
Verse 2, Open Ending, Verse 2, Closed Ending
For further reading:
Timothy McGee, Medieval Instrumental Dances.