Mac OS X: share your internet connection wirelessly

There is no WIFI available in my office. The internet connection of my Mac is via Ethernet. I want to share my internet connection to my android phone so that it can download apps. The following instructions shows how I share the (Ethernet) internet connection of my Mac to my mobile phone via wireless/WIFI.

1. Open System Preferences and select Sharing
   
   
2. Select Internet Sharing, set "Share your connection from Ethernet", "To computers using Wi-Fi", then click Wi-Fi Options... button
   
   
3. In the Wi-Fi options window, set the Network Name, Security and Password, then click OK button:
   
   
   
4. Tick Internet Sharing, in the confirm window click Start button:
   
5. Now the WiFi hotspot is running, you should see the green light and Internet Sharing: On
   
   

Trouble shooting

• The client computer/mobile phone will fail to connect to the WIFI network (fail to request IP address from the network) if the your Mac has Firewall turned on and it is configured to blocking all incoming connections (It will of course block the DHCP requests from the WIFI clients). To Resolve it, you need to untick the Block all incoming connections option:
  1. Open System Preferences then Security & Privacy, 
     
     
     
     
     
  2. click Firewall Options... button:
     
     
     
     
  3. Untick Block all incoming connections