Before you upload your video, make sure you've added a horse to your profile.
Go to My Profile and choose the My Horses tab. Click the Add Horse button and complete the form with name, stable name, height, breed, owner information and include a photograph.
Mobile Users
If you're using a mobile phone to update your profile and add a horse, there is currently an issue pressing the SAVE button (hidden by the messenger button). You can get around this by placing your cursor in a text box and pressing GO on the on-screen keyboard.