Update README.md

README.md

@@ -1,2 +1,27 @@
 # mkr-bin-client
 
+Command line client for [mkr/bin](https://github.com/MKRhere/bin). Uses
+[bin.mkr.pw](https://bin.mkr.pw) as the default instance.
+
+## Requirements
+
++ xclip (for copying url into clipboard)
++ curl
+
+## Usage
+
+Copy `mbin.sh` to your PATH or add an alias to point to the absolute path of
+`mbin.sh`.
+
+```bash
+  some_command | mbin.sh
+  mbin.sh # Opens in interactive mode.
+```
+
+## Customization
+
++ To use custom instance, export `MKR_BIN` variable.
+  + Add `export MKR_BIN="https://bin.example.com/"` (Ensure to keep the
+    trailing slash) in your shell rc (`~/.bashrc` if using bash).
++ To use an editor other than vim in interactive mode, export `EDITOR` variable.
+  + Add `export EDITOR=micro` in your shell rc (`~/.bashrc` if using bash).