First things first. You need to get into the Android System recovery to Hard reset your android phone. There is a specific method to do this for different manufacturers
Press and hold Volume Up + Home key then also hold Power key. Keep holding all the three buttons till you feel the vibration or see samsung logo. As soon as you see the logo release the Power Key and keep holding the Volume Up key and Home Key. After few seconds you will land up into Android System Recovery.
Hold down the Volume Up first keep holding it then, now also hold power key. keep holding both the keys till the phone turns on into android system recovery mode. Now use Volume Up and Down Key to highlight recovery mode and then press Power Key to Select it
Hold down the Volume up + Volume Down Key simultaneously, now also hold the Power key as well, keep holding all the three buttons until you land up in recovery mode. The Micromax phone will ask you to press the Volume Up key once to select the Recovery Option
Press Volume down + Power Key till the phone vibrates. Now select the recovery option by moving Volume Up and Down Key and selecting the option by power button. You will an Android guy with an exclamation mark. Then Press and hold power key then Volume Up key to land up into Android recovery mode.
Now for any reason you do not see your phone in the above mentioned Manufacturers you can always Google How to Hard Factory Reset “Your Device and Model”
Once you are in recovery mode, the touch screen does not work. Use Volume Up and Down Key to highlight “Wipe Data/ Factory Reset” and then press Power key to Start Factory Data reset. For Micromax devices you can navigate the options using Volume Up and Down Key and to select Factory Data Reset you have to press Menu Key present on extreme left bottom.
Once factory data reset is done, your android phone will be as new as it can get. You can start using your device again.