To find your operating system of your phone, please go to Menu/Options/About from your blackberry and look for the v5.0.0 etc. Your OS is after the v.

There are two ways to download a theme via OTA (Over the Air).

From Blackberry Browser:
To download a theme to your blackberry using an OTA link, simply point your blackberry browser to the page of the theme and click on the "OTA" link that is appropriate for your phone model.

From Computer Browser:
From the internet browser, right click on the OTA link that is appropriate for your phone model and select "copy shortcut". Paste it in an email and email link to your blackberry. Open link and start download.

How to Install a Blackberry theme through the .zip file:

1. Download and Extract the .zip file to your computer. This file should contain the .alx or .cod files.

2. Connect your blackberry phone using a USB cable to your computer.

3. Start the Desktop Manager on your PC. Using the application loader on Desktop Manager, use the browse to locate the .alx and .cod files that were just extracted and select next. Once it has loaded, click next to install and reboot your device. T

4. To find the theme you just downloaded, go to Options<Themes and scroll to the theme you downloaded.


*If you do not see the theme under Options<Themes, you selected the wrong OS version for you phone.  

In the Message List:  
   
    ALT+i:  Displays only incoming mail. 
    ALT+o: Displays only outgoing mail (messages you have sent). 
    ALT+p: Displays phone log messages. 
    ALT+s: Displays SMS messages.
    ALT+v: Displays VoiceMail messages.

In the Home Screen:
  
1. To display the signal bars in the numeric form: press ALT+NMLL, press again to switch back.

2. Press ALT+CAPS+h to display the Help Me screen. (This screen shows the version, application version, PIN #, IMEI #, signal strength, battery level, fille free/total.)    

3. Press ALT+CAP+BACKSPACE to reboot your device