First of all, take your phone out of the standby mode. For this, you need to push the main menu button right at bottom of the screen.
Enter the password, if you have put any screen lock. Once you reach the main screen, the procedure is pretty easy.
Tap ‘Keypad’ from the main screen of the phone. Type the phone number that you want to add to the contact list.
To add the number, push the icon that shows a person.
As soon as you tap this icon, a new screen will appear in front of you. Here you need to add the relevant information about your contact, such as name, email address and any other phone numbers.
If you just want to add another phone number to an already existing contact, select the "Add to Existing Contact" option. The entire phonebook will popup and you just need to select the name of that particular contact.
One can also add a contact from the recent call list. For this, you just need to open your call log and navigate to the number that you are interested in.
After tapping the blue arrow next to it, select the option that says ‘Create New Contact’. The rest of the procedure is same. After adding the relevant information, tap on ‘Done.
You can also add the number from the text messages. First of all, open your messages and select the conversation with that contact.
Use your thumb to scroll to the top of the conversation, where you will see "Add to Contacts" option on the upper-right corner of the screen. Push the button and after adding the information, select ‘Done’.