diff --git a/README.md b/README.md
index e2d7c39..697dc27 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,25 @@
 # node.js-parameter-handler
 parameter handler
+
+
+# how to use
+
+
+```
+# package.json
+{
+    "extra": {
+        "node_parameter_handler": [
+            {
+                "source": "tests/fixtures/settings.json.dist", # source 
+                "output": "var/settings.json",                 # output
+                "envMap": {
+                    "touched": "BASE_URL", # json path to ENV VARIABLE
+                    "test.touched": "PWD",
+                    "test.test.touched": "HOME"
+                }
+            }
+        ]
+    }
+}
+```