Unlike your typical computer where you usually shutdown properly, I cannot rely on this during the use of my Intel Edison. If the Intel Edison is improperly shutdown too many times, data corruption in the file system leading to unbootable system may result. So we should use a read-only file system.
This version has been adapted from my Raspberry Pi Arch Linux's instructions.
#Update everything first
opkg update
opkg upgrade
#Adjust /etc/fstab, add/modify to the following hashed lines. Mount certain directories to RAM disk.