First of all, select the MP3 file which you want to convert. You can simply select the file from your mouse. After selecting the file, right-click on it and a window will appear on your screen. You have to select the ‘Get Info’ from that menu.
Now, when the new window will open, just click on the tab ‘Options’. After that, you have to navigate ‘Start Time’ and ‘Stop Time’ fields. You will have to place a check mark in both the fields so as to select the starting and ending time of your ringtone. Then, click ‘OK’.
You have to go back to the MP3 file. Right-click on the file again and select ‘Convert Selection to AAC’. Your iTunes will automatically make the changes to that file (as per your set time limit). This file is now different from the original file.
Then, go to the music folder in iTunes and find that new file which you have created. Drag that file on your desktop with the help of your mouse. After that, go back to iTunes and just delete the copy of the version which you dragged on your desktop by just right-clicking on it and selecting ‘Delete’ option.
Now, go to your desktop and right-click on the icon of the file which is on the desktop. Select ‘Rename’ and just change the file extension from ‘.m4a’ to ‘.m4r’.
Just drag the file back to iTunes and connect your iPhone 2.1 to your PC with the help of your USB cable. Then, ‘Sync’ your data by clicking ‘OK’ and your ringtone will move to your iPhone.