$ tune2fs -l /dev/sda6 | grep "Default mount options:"
Default mount options:    user_xattr acl

$ setfacl -m "u:username:rwx" /path/to/folder

$ setfacl -m "g:groupname:rwx" /path/to/folder

$ setfacl -m "o:rwx" /path/to/folder

$ getfacl /path/to/folder

$ setfacl -m u:username:rwx,g:groupname:rwx,o:rwx /path/to/folder

The new object inherits the default ACL of the containing directory as its
 access ACL.

 If no default ACL is associated with a directory, the mode parameter to the func‐
 tions creating file objects and the file creation mask (see umask(2)) are used to
 determine the ACL of the new object:

 The new object is assigned an access ACL containing entries of tag types
 ACL_USER_OBJ, ACL_GROUP_OBJ, and ACL_OTHER. The permissions of these entries
 are set to the permissions specified by the file creation mask.

$ setfacl -d -m u::rwx,g::rwx,o::rwx /path/to/folder

$ setfacl -m default:u::rwx,default:g::rwx,default:o::rwx /path/to/folder

$ setfacl -d -m o:--x /path/to/folder

$ getfacl /path/to/folder
# file: path/to/folder
# owner: c0rp
# group: c0rp
user::rwx
group::rwx
other::--x
default:user::rwx
default:group::rwx
default:other::--x

$ setfacl -b /path/to/folder

$ setfacl -d -m u::rwx,g::rwx,o::rwx /path/to/folder