1. Open "Settings":

2. Select "More...":

3. Select "VPN":

4. If you do not have a screen lock installed, then set it in one of the suggested ways:
5. Click "Add VPN network":

6. On the screen "Edit VPN network":
- in the "Name" field, enter the name of the connection, for example, "VPN-SMART"
-in the "Type" list select "L2TP/IPSec PSK"
-in the"Server address" field enter given ip-address of your VPN server
-leave fields "L2TP secret" and "IPSec identifier" empty
-in the "IPSec pre-shared key" enter given IPSec pre-shared key and click "Save":

7. Now you will see the newly created connection "VPN-SMART". Click on it.

8. Enter given Username and Password. Check "Save account information" checkbox and click "Connect" to get connected:
From now, after VPN-connnection has already been created, it can be turned on/off in "Settings"->"Wireless & networks"->"VPN":