Open Excel and enter your phone numbers in the correct format. All Malaysian mobile numbers must begin with prefix 60 (e.g. 60123456789, 60192345678).
To convert numbers to the 60-prefix format automatically:
In the Format Cells dialog, select "Custom" and enter the format: 60########## (60 followed by 10 # symbols). Click OK. All numbers will be prefixed with 60.
Go to File → Save As. In the format dropdown, choose CSV (Comma delimited) (.csv). Click Save.
Excel will prompt you to confirm saving in CSV format — click Yes to proceed. Your CSV file is now ready to upload to iSMS.