diff --git a/README.md b/README.md
index 30f62e9..cb6f031 100644
--- a/README.md
+++ b/README.md
@@ -20,32 +20,39 @@ The script uses rsync to actually run the backup, so you will have to install it
 sudo pacman -Syu rsync
 ```
 
-Optional dependencies are systemd-python to enable using systemd journal for logging, dbus-python for desktop notifications, and paramiko for remote backup.
+Optional dependencies are systemd-python to enable using systemd journal for logging, dbus-python for desktop notifications, and paramiko (version 3.2 or later) for remote backup.
 
 ## Install
-To install the program, first clone the repository:
+For Arch Linux and Arch-based distros, two packages are available in the AUR (aur.archlinux.org):
+- **simple_backup** for the release version
+- **simple_backup-git** for the git version
+
+To install it from source, first clone the repository:
 
 ```bash
 git clone https://git.shouldnt.work/fuxino/simple_backup.git
 ```
 
-Then install the tools required to build the package:
-
-```bash
-pip install --upgrade build
-```
-
-Finally, run:
+Then build the package (this requires the Python `build` module, e.g. the python-build package on Arch Linux):
 
 ```bash
 cd simple_backup
 python -m build --wheel
-python -m pip install dist/*.whl
 ```
 
-For Arch Linux and Arch-based distros, two packages are available in the AUR (aur.archlinux.org):
-- **simple_backup** for the release version
-- **simple_backup-git** for the git version
+Many distributions don't allow installing packages with pip into the system Python ("externally-managed-environment" error).
+In that case, install the wheel in a virtual environment, for example with pipx:
+
+```bash
+pipx install dist/*.whl
+```
+
+Optional dependencies can be installed as extras, for example `pipx install 'dist/simple_backup-<version>-py3-none-any.whl[REMOTE]'` (available extras: JOURNAL, NOTIFICATIONS, REMOTE).
+
+## Running as root
+To back up files that your user can't read, run simple_backup with sudo or doas.
+In that case the user who ran the command is detected automatically, so that '~' (in the inputs and in the default configuration file path) refers to that user's home directory, not root's.
+When running as root in other ways (e.g. from a systemd service), specify the user with the --user (or -u) argument.
 
 ## Old backups
 The number of old backups to keep can be set with the --keep (or -k) argument (or in the configuration file).
@@ -57,8 +64,16 @@ The only rsync error that is ignored is return code 24 (source files vanished du
 > This feature is experimental
 
 It's possible to use a remote server as destination for the backup. Just use the --ssh-user and --ssh-host arguments (or set them in the configuration file).
+Both are required: if only one of them is set, simple_backup exits with an error.
 For this to work, rsync must be installed on the server too.
 
+The output directory is a path on the server. A leading '~' and relative paths refer to the user's home directory on the server.
+On the command line, quote '~' so that your local shell doesn't expand it:
+
+```bash
+simple_backup --ssh-host server --ssh-user user -o '~/backups'
+```
+
 ### Server authentication
 The best way to handle the authentication is to have an ssh agent running on your system, otherwise if a passphrase is necessary to unlock the ssh key, it will be necessary to enter it more than once.
 If needed, it's possible to specify the ssh key location with the --keyfile argument or in the configuration file.