Install OSXFUSE
Most instructions on the web have you install OSXFUSE from the github link, but I've had better luck with homebrew:
brew install osxfuse
Install SSHFS
Install sshfs from the terminal
brew install sshfs
Mount the filesystem
before you can mount the Beaglebone's file system you'll need to make a target for it on your Mac
mkdir ~/beaglebone-shared
Now you can mount to it
sshfs root@192.168.7.2:/ /Users/<youraccount>/beaglebone-shared
...of course you'll want to replace the ip address with the one of your Beaglebone, and youraccount with your account on your Mac.
You'll be asked for the root password of your Beaglebone but once given you'll be able to access all the files on your Beaglebone! Test this with
ls ~/beaglebone-shared
Unmount the filesystem
After you're done working, you'll want to unmount the Beaglebone's filesystem. Be sure your local shared directory is not in use (including any open terminal sessions that might be sitting in that directory) and then
sudo umount ~/beaglebone-shared