It sounds as if you simply want to pause and resume your mirror. Have you seen this link yet? http://msdn.microsoft.com/en-us/library/ms190664.aspx
The gotcha with this would be the length of time you expect to have the mirror paused. If you take too long then the principal server could experience a large amount of transaction log growth. if you do not expect to be paused for a long period of time, then you should be fine.
If you feel that you must break the mirror and resume later, then you should do the following:
Break the mirror using this against the principal:
ALTER DATABASE SET PARTNER OFF
If you are concerned that your maintenance will take a long time, then you should perform regular transaction log backups, so as to make certain the log does not grow out of control and fill up your disks. however, the more trx log backups you have, the more you need to recover to the mirror later.
After you have restored the trx logs, you should be able to get mirroring running again.
Another option would be to reinitialize everything, but I don't know how big of a database this is, it may be too much for you to restore, so trx logs may be the better option.
This link explains it best: http://msdn.microsoft.com/en-us/library/ms189112.aspx
And this link covers more topics: http://msdn.microsoft.com/en-us/library/ms175059.aspx
HTH
