diff --git a/Readme.md b/Readme.md
index e69de29..81b6cbe 100644
--- a/Readme.md
+++ b/Readme.md
@@ -0,0 +1,8 @@
+# How to use it
+This example pushes the measured data using HTTP POST request on ThinkSpeak server.
+Thus, modify the APIKey in `thingSpeak.cpp`, then compile using:
+
+```bash
+g++ thingSpeak.cpp network/SocketClient.cpp - o thingSpeak
+./thingSpeak
+```
diff --git a/thingSpeak.cpp b/thingSpeak.cpp
index 779c2fc..1b7b7cf 100644
--- a/thingSpeak.cpp
+++ b/thingSpeak.cpp
@@ -33,7 +33,7 @@ int main() {
    head << "POST /update HTTP/1.1\n"
         << "Host: api.thingspeak.com\n"
         << "Connection: close\n"
-        << "X-THINGSPEAKAPIKEY: Z7PNWRYKDEBRX5F7\n"
+        << "X-THINGSPEAKAPIKEY: 621LKPK58GD7PHSB\n"
         << "Content-Type: application/x-www-form-urlencoded\n"
         << "Content-Length:" << string(data.str()).length() << "\n\n";
    sc.send(string(head.str()));