ExXB
Go to
www.ba.com, click on 'Executive Club', enter your Exec number and pin then 'Log In', on left side click on 'Contact Executive Club', scroll down to bottom of page and click on 'Contact Us', scroll down to the botton and in the 'Contact BA by email' box click on '>Go to email form', fill in the form, click on 'send'.
BA Miles can be redeemed on line with no charge. There is a tool which tells you which flights and destinations have BA Miles seats available.
Hope this helps
Dave