I'll leave below also a cheat sheet :)
Create a soft or symbolic link?
sudo ln -s /path/to/source/file
Note: this works if you both nodes are below you in the same tree. You can use relative notation
-scommand makes it a symbolic link
-nmakes it possible de create a folder-type symlink
Note that wherever you currently are is where the shortcut will be created.
Find a document on the server:
sudo find / -name foo.txt (foo.txt is the file to search)
Get full path of a file/folder
readlink -f file.txt
Switch to root:
Switch user between terminals:
su - user2
sudo rm -rf folderName