Linux and OSX
In the command line, create a new directory in the location of your choice on your computer, then run
sshfs [REMOTEUSER]@SERVERNAME:[PATH] DIRECTORY .
mkdir newDir && sshfs firstname.lastname@example.org: newDir
To unmount the sshfs directory, run
umount DIRECTORY . NOTE: you need elevated privileges to unmount the directory, so make sure you actually wanted to mount it in the first place.
Open File explorer, right click on "My PC" in the sidebar on the left, and then click "Map network drive".
In the dialogue, choose whatever drive letter you want to assign the remote drive to in the dropdown. In the textbox, type
\\sshfs\[remoteuser]@SERVER:[PATH] and check "Connect using different credentials" before pressing finish. You should now see the folder in File Explorer.
NOTE: there are no dependencies server-side other than an ssh server.
Install SSHFS from your package manager of choice. Ex:
sudo apt-get install sshfs
Download OSXFUSE and SSHFS from the OSXFUSE Website
Note: FUSE is not supported by the Windows Subsystem for Linux on Windows, so you can only use SSHFS through normal Windows.