Hi Abigail
You need to make sure that the pages cannot get lost at the sorting office, if you have a hole punch, punch a hole in the top corner and attach the pages together with a piece of string/ribbon so that they can be easily detached and put through a scanner.
What some members have done is cut out the address on the envelope and stick it on to another larger envelope or just sellotape the old envelope on to the new envelope.
Don't forget to send it by recorded delivery.
Gary
Nothing on this board constitutes legal advice - always consult a professional about specific problems