How to Use Your Android Phone as a Modem??

What You’ll Need??
In order to tether your phone to your laptop as a data modem, without having to root your device, you’ll need the following things on hand:

Your Android phone
Your laptop, netbook, or desktop computer you wish to tether
A USB sync cable for your Android phone

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Installing PdaNet on Your Android Device
First, instal this app on your computer it will ask to connect your device then automatically it install the app on your device.Open it

Tap “Enable USB Tether” to turn it on. You can also do a wireless tether using Bluetooth but we’re skipping that for now. Bluetooth can be so finicky we don’t want you to get mired down in trying to figure out why your Bluetooth connection is acting up. When you enable it for the first time it will prompt you, as seen in the last panel, to download the desktop software. This is handy for those times you’re stuck without any internet but the internet on your phone and need to download and transfer the application to your computer. In our case we clicked No, since the computer we’re configuring already has internet access and we can download the desktop app that way.
Installing PdaNet on Your Desktop

Installing the desktop software is pretty uneventful and requires no configuration. There are, however, a few things to watch out for.
If you have the Android Deveopment toolkit on your computer (as you may have if you followed along with our guide to remote controlling and viewing your Android phone) you’ll run into two potential errors. If the abd.exe is running you’ll have to kill the process with Task Manager. You’ll also get a notification that there are Android drivers already installed on the computer. When in doubt overwrite the drivers with the new ones from PdaNet to ensure you can connect to the internet properly. After the installation you’ll see the PdaNet icon in the corner.