How to connect Redmi 1S to PC?

You will need Mi Phone tool to be able to connect your Redmi 1S to PC. Download the tool from the link - http://enbigota.d.miui.com/tools/MiPhone20140509.exe
Make sure your device drivers are properly installed. You can check the drivers from this link - http://en.miui.com/forum.php?mod=viewthread&tid=26278&page=1#pid505593
If it still does not connect, you may need to update your phone to the latest firmware. Also make sure you have enabled USB Debugging. You can do it from Developer options in the settings menu.

If you want to connect your Xiaomi Redmi 1S to your PC, you need to download Xiaomi Redmi 1S PC Suit.

Download Link Xiaomi Redmi 1S PC Suite
http://goo.gl/KnxCgg

Download Link Xiaomi Redmi 1S USB Drivers
http://goo.gl/XnGWcR

After downloading you can install it on your computer and change the language from Chinese to English.
That's it. Now connect Redmi 1S with your computer.