My Macbook won't start, and I must reinstall the disk. I haven't used time machine to back up, and I want to use an external drive to back up now. How can i do this from the utilities page?

Question

I am currently in Zambia on missions work and my computer is constantly exposed to heat. I have just been trying to avoid using it during the hottest part of the day. Today though, I started it up and it was stuck on the grey page with the rotating circle for over an hour, then once the circle left, it remained frozen on the gray page. I used command + r at startup to go to the utilities page to analyze the disk. It found that there were problems with the disk, but then it could not fix those problems and told me to backup as much information as I could and reinstall or redo it all. I haven't ever used time machine to back up any of my information, but i have an external drive that I can use right now to backup my files. I can't get into my computer though to backup the files. How can I use this external drive to backup my files while the computer is currently messed up? Please help.

Answer 1

Emergency Backups (Data Recovery)
A)          Format an external disk:
          (This will erase all data on the external disk.)
          Boot in recovery mode (power then Command-R).
                    Alternative: Network recovery boot (power then Command-Option-R keys)
          To format (and erase) the destination recovery disk:
          Plug in the drive you are about to erase.
          Select the volume that is NOT your system disk.
          Click on Partition.
          Pull down under Partition Layout to 1 Partition.
          Click on Options…
          Select GUID Partition Table.
          Name: Emergency Backup (or whatever you prefer)
          Format: Select Mac OS Extended (journaled)
          Click Apply.
          Click Partition.
B)          Try to boot in Safe Mode (power then Shift key).
          (This will be a slow boot.  Be patient.)
          If it won’t boot in Safe Mode, jump to C.
          If it boots in Safe Mode, try to boot in normal mode.
                    If that fixed your problem then start a Time Machine backup.
                    http://support.apple.com/kb/ht1427
                    https://discussions.apple.com/docs/DOC-4055
          If not, boot in Safe Mode again.
          Go > Computer.
          Double click on the system disk.
          Drag the Users folder to the recovery disk.
C)          To clone the disk:
          Boot in recovery mode.
          Select Disk Utility.
          Try to repair the system disk twice.
          Whether or not the repair succeeds:
          Drag and drop the system disk to Source:
          Drag an drop Emergency Backup to Destination:
          (Take care not to reverse this order.)
          Click Restore (the lower Restore button).
Once your system is healthy, maintain two reasonably current backups.  (Time machine restores can fail.)
Create either two Time Machine backups (good) or one or more Time Machine backup(s) and one or more bootable-clone backup(s) (better).
          Use Carbon Copy Cloner or SuperDuper! to create bootable-clone recovery disks.
          See https://discussions.apple.com/docs/DOC-3045
          and https://discussions.apple.com/docs/DOC-6031