diff --git a/IoT-Wireless/Lab-I.adoc b/IoT-Wireless/Lab-I.adoc
index 60a9c18..6e6cd45 100644
--- a/IoT-Wireless/Lab-I.adoc
+++ b/IoT-Wireless/Lab-I.adoc
@@ -37,8 +37,8 @@ https://en.wikipedia.org/wiki/Contiki[^]
 ----
 unzip InstantContiki2.7.zip
 vmplayer
-----
 Start  image
+----
 
 == Log In
 When the login screen appears, log in to Instant Contiki:
@@ -122,6 +122,18 @@ We have now created our first simulation in COOJA. However, the simulation does
 
 To add nodes we need to first create a node type, and then add nodes to the simulation.
 
+
+[NOTE]
+====
+- The *Network* window,  at  the  top  left  of  the  screen,  shows  all  the  motes  in  the simulated network
+- The *Timeline* window, at the bottom of the screen, shows all communication events in the simulation over time   
+- The *Mote* output window, on the right side of the screen, shows all serial port printouts from all the motes.  
+- The *Notes* window on the top right is where you can put notes for your simulation.  
+- And the *Simulation* control window is where you start, pause, and reload your simulation.
+====
+
+
+
 === Create a node type
 
 Any simulated node in COOJA belongs to a node type.  
@@ -226,6 +238,55 @@ A  node  in  the  grey  area  cannot  receive  packets  correctly
 
 
 
+===  Extend the hello-world example
+
+- Create a folder 
+- Copy+paste the *contiki/examples/hello-world* folder in your new folder.  
+
+==== Sensors, LEDs and Button
+
+We will extend the Hello World program to let it print sensor data and toggle the leds when the button is pressed.  
+
+.ADD
+----
+#include "dev/button-sensor.h"
+#include "dev/light-sensor.h"
+#include "dev/leds.h"
+#include <stdio.h>           /* For printf() */
+----
+
+
+
+Sensors needs to be activated in the main process:
+
+
+[source,bash]
+----
+SENSORS_ACTIVATE(button_sensor);
+SENSORS_ACTIVATE(light_sensor);
+----
+
+
+To print out the current light sensor value:
+
+[source,bash]
+----
+printf("Light: \%u\n", light_sensor.value(0));
+----
+
+To wait for an event and check if this event is a button press:
+
+[source,bash]
+----
+PROCESS_WAIT_EVENT_UNTIL(ev == sensors_even && data == &button_sensor);
+----
+
+To toggle LEDs:
+
+[source,bash]
+----
+leds_toggle(LEDS_AL
+----