hi dear friend , First you need to go in to the setting part of your windows, add Farsi (Persian) to your languages in your pc, then you need to have Farsi font for your WORD software. I can send you the fonts if you can't download it from the net, my friend. Feel free to ask me for help at any time. :) see you Hiva

بعد از اضافه کردن زبان فارسی به سیستم عامل خود، با نگه داشتن همزمان Alt + Shift سمت راست می تونید بین زبانها سوئیچ کنید

Hi, You can also try one of thos virtual keyboard in Farsi. Here are some samples: http://gate2home.com/Farsi-Persian-Keyboard or http://www.howtosayin.com/virtual-keyboards/persian-virtual-keyboard.php