How can I schedule an appointment at the Battersea Apple Store?

You can use this link, Genius Bar Reservation and Apple Support Options - Apple

Sheppez wrote:

I want to make an appointment this weekend at the Battersea store this weekend

This is a user to user technical forum there is no Apple here.

No one can assist with scheduling an appointment.

Go into the store and see if they can help or give them a call.