I use folders in outlook to store important emails but these emails are sent
to me from different people and have different writing in the subject
section. I would like to categorise this information or at least and a
comment for each email that can be used as a reference to the information in
the email for me only.

For example:
ORIGINAL EMAIL SUBJECT: Andrew FYI.
SUBJECT OR COMMENT I WANT FOR THE EMAIL: Light Repairs

Is there a way i can create a comment/discription message for each email in
the folder or change the subject without replying or fowarding the email to
myself again?

Thanks,
Andrew