Use the mount command to mount a NFS filesystem from another machine:
mount porky:/mnt/export /mnt/local
In this command, porky is the hostname of the NFS fileserver, /mnt/export is the filesystem that porky is exporting, and /mnt/local is a directory on my local machine where I want to mount the filesystem. After the mount command runs (and if I had the proper permissions from porky) - voila! - I can enter `ls /mnt/local' and get a listing of the files in /mnt/export on porky.