The AutoCorrect feature in Word 2013 can build common fractions for you. Actually, it doesn't build them as much as it pulls them from a set of existing fraction "characters." Sadly, Word has only a few of these fraction characters. When you need your own, specific fraction, such as 3/64, you can create it this way:
Press Ctrl+Shift+= (the equal sign).
This keyboard is the shortcut for the superscript command. This will allow you to type your numerator.
Type the numerator — the top part of the fraction.
For example, type 3 for 3⁄64.
Press Ctrl+Shift+= again.
This turns off the superscript. Now you can move on to the next part of your fraction.
Type the slash mark (/).
This gives you the division bar of your fraction.
Press Ctrl+=.
This will turn on the subscripting for the denominator.
Type the denominator — the bottom part of the fraction.
For example, type 64 for 3/64.
Press Ctrl+= to turn off subscripting.
You now have a completed fraction and you didn’t have to write it in.