Help Center

Go to the page of one of your stallions that is above 2,5 years old. There will be a button on his page that says Cover a mare. Click that, choose either public, reserved for a mare of a player or reserved for one of your own mares, choose a price and click Confirm.
Objective done :)

You go to a horse and there is a thing you press and to things will apear and public coverings or reserved covering