Convert all the footage to a smaller size (960x540 for instance) with heavy compression, have him/her send you the footage, you edit it and send back a project file, then connect it to the original HD files and paste the cut into an HD timeline.
Or FedEx a hard drive.
--------------------
Angelo Lorenzo
Need to encode ProRes on your Windows PC?
Introducing ProRes Helper, an awesome little app that makes it possible
Fallen Empire Digital Production Services - Los Angeles
RED transcoding, on-set DIT, and RED Epic rental services
Fallen Empire - The Blog
A blog dedicated to filmmaking, the RED workflow, and DIT tips and tricks
Can your post production question fit in a tweet? Follow me on Twitter