Update readme

README.md

@@ -37,15 +37,17 @@ Assets (including OTA updates) are constructed specially and cannot be extracted
 ```shell
 # Decrypt if necessary
 aea decrypt -i <path to AEA> -o <decrypted asset archive> -key-value 'base64:<key in base64>'
-./aastuff <decrypted asset archive> <output folder>
+./aastuff -i <decrypted asset archive> -o <output folder>
 ```
 
 `aastuff` can also handle asset archives that are not already decrypted:
 
 ```shell
-./aastuff <path to AEA> <output folder> <key in base64>
+./aastuff -i <path to AEA> -o <output folder> -k <key in base64>
 ```
 
+Run `./aastuff -h` for full usage information.
+
 ## Notes
 
 `aastuff` uses `AAAssetExtractor`, functions from `libAppleArchive` in order to extract asset archives. However, it is a pretty barren API and does not offer things like selective extraction.