Simply click the download button on the right to begin the process.
Then follow the screenshots as given below:

Simply double click the SoftPhone icon on your desktop.
Then follow the screenshots as given below:
Click Save to save the file onto your computer.
Locate the Desktop on your computer and click Save.
When the download is complete, click the Close button.
Press Run.
Select your language, then click OK.
Close all other windows and then press Next.
Select I accept the license agreement and click Next.
Click Next.
Click Install.
Click Finish.
Enter your account number and PIN (which is given to you when you buy credit).
Then click OK.