diff --git a/README.md b/README.md
index 872a514..453ebb6 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,48 @@
 # settingFiles
+
+Personal dotfiles and OS setup scripts. This repository separates OS/target
+environments by **branch** instead of by directory — clone the branch that
+matches your target machine, not `master` directly.
+
+## Branches
+
+| Branch | Purpose | Notes |
+|---|---|---|
+| `master` | Common base | Shared dotfiles only; starting point for new OS branches |
+| `arch` | Arch Linux (x86_64) | GNOME desktop, Steam, hibernate support |
+| `macOS` | macOS | Homebrew, Karabiner-Elements |
+| `ubuntu` | Ubuntu | |
+| `alpine` | Alpine Linux | Docker container use |
+| `raspi` | Raspberry Pi OS (Debian-based, `apt`) | Headless/CLI |
+| `raspi-arch` | Arch Linux ARM on Raspberry Pi | Headless/CLI |
+
+`.vimrc` is identical on every branch, and the bulk of `.zshrc` is shared too —
+branches only differ in a small OS-specific tail (PATH entries, keychain/GPG
+setup, plugin list, etc.). `master` holds the canonical copies of these
+shared files. When editing the shared portions, port the same change to the
+other branches by hand; there is no symlink/build step tying the branches
+together, so nothing will warn you if they drift.
+
 ## Installation
-Install zsh, tmux, neovim, git curl with your package manager.
 
-Then,
+Install `zsh`, `tmux`, `neovim`, `git`, and `curl` with your package manager
+first.
+
+Then clone the branch matching your target OS (see the table above):
+
+```
+git clone -b <branch> https://github.com/LJLee37/settingfiles.git ~/gitRepos/settingfiles
+```
+
+and run `set.sh` from inside the repo.
 
-`git clone https://github.com/LJLee37/settingfiles.git ~/gitRepos/settingfiles`
+After running `set.sh`, enter `nvim`, then run `:call coc#util#install()` if
+you hit a coc error.
 
-And run `set.sh` in the repo.
+## Raspberry Pi OS install order
 
-After running `set.sh` file, enter `nvim` to enter neovim, then enter `:call coc#util#install()` if you encounter coc error.
+1. Flash Raspberry Pi OS with Raspberry Pi Imager and boot the Pi.
+2. Run `install.sh` (base packages, git identity, GPG signing key).
+3. Run `set.sh` to pull in dotfiles.
+4. `backup.sh` makes a full-system + firmware backup and copies it to a LAN
+   host — check the destination host/path before running it.
diff --git a/set.sh b/set.sh
index 971aaa6..160fc95 100755
--- a/set.sh
+++ b/set.sh
@@ -10,9 +10,9 @@ curl -sL install-node.now.sh/lts | sudo bash
 curl --compressed -o- -L https://yarnpkg.com/install.sh | bash
 mkdir ~/.config
 mkdir ~/.config/nvim
-cp ~/gitRepos/Personal/settingfiles/init.vim ~/.config/nvim/init.vim
+cp ~/gitRepos/settingfiles/init.vim ~/.config/nvim/init.vim
 mv ~/.zshrc ~/.zshrc.bak
-cp ~/gitRepos/Personal/settingfiles/.zshrc ~/.zshrc
+cp ~/gitRepos/settingfiles/.zshrc ~/.zshrc
 ln -s ~/.config/nvim/init.vim ~/init.vim
 nvim +PlugInstall +qall