How to rollback from Windows 10 mobile to Windows phone 8.1

As Microsoft is successfully running it's insider program many windows phone users are testing the technical preview of new upcoming windows 10 mobile.
Windows 10 is Microsoft's new and latest operating system in history of information technology devices. 
The main reason is that Windows 10 can be installed on many device like as a phone, a computer, laptop and also even on a fitness band like as Microsoft band 2. Microsoft has optimized it's operating system so it can be used among all present device.
 Many people already took advantage of insider program to test this new edition of operating system on their computer and phone. But off-course it is a still under development so there is also a lot's of chances of bugs. 
A fewpeople who used this OS on their windows phone like as a lumia are tired of it and want to rollback to their stable operating system. Due to less-stability and bugs
This guide will help you in rolling back to that stable operating system on phone. On computer it is much easier to rollback to older version. Rolling back is not much difficult in windows phone too.

So here are the Steps:
1: First thing is a PC. A PC running windows (Any but windows 8.1 is best);
2;Get a data cable which must be official or enough good so no problem occur during flashing process.
3: Download latest version of Windows device recovery tool software.
(It is recommended to download this tool as online installer so you can always get latest version which means very low chances of any error)
4: After downloading and installing this software. Connect your phone with data cable.
5: If your phone is not recognized here then click on my phone is not detected.
6: Follow on-screen instruction to1` get phone detected.
7: After detection this will take some time in reading phone status.
8: Now click on re-install software button. Accept terms (if you are agree).
(This will say about losing of all previous data. Make sure to backup all data before this process).
9: Now download for firmware will start. This process can take time and depends upon your internet connection speed.
(Remember this software won't work if you haven't got an internet connection.)
10: After downloading the flashing will be started and in about 10 to 15 minutes this shall be done.
11: Now you will experience a new or reset lumia welcome. Setup according  to your needs. Done.

Make sure to follow all steps correctly. Some times error is occured due to bad data cable, damage in firmware during downloading process. In this way phone can be bricked. This is just a guide for recovering your phone. I am not responsible for any damage ot loss to your phone.