Steps to follow:
Step 1: Download Rufus if it is not already available. Besides the usual installation version, Rufus also has the Portable version. Download the Portable version if you do not want to install software on the system.
Step 2: Start Rufus and plug the USB drive into the computer. You will immediately see it appear in the top drop down menu at the main interface of Rufus. When you see the drive, click the Select button.
Step 3: In the Browse window, go to the location where you saved the ISO file, click it and click Open.
Step 4: This is an optional step. If desired, click the tick icon next to the Boot Selection option to calculate and view the MD5, SHA1 and SHA256 checksum of the ISO file. This is useful for verifying if the ISO file is corrupted anywhere.
Step 5: Select MBR from the Partition Scheme menu and the BIOS or UEFI from the Target System menu. If you are trying to use this USB boost on an older operating system, check the Add fixes for old BIOSes option under Advanced Drive Properties.
Step 6: This is an optional step. You can change the name of the USB drive at the Volume Label field. Also, under Advanced Format Options, you need to make sure that the Quick Format option is checked. The name says it all, Quick Format formats the drive faster by skipping the process of checking for bad sectors.
Step 7: Then, click the Start button.
Step 8: Depending on the ISO file, Rufus may ask you to download additional files. For example, to create an Ubuntu drive, Rufus prompts you to download a new version of Syslinux. Just click the Yes button and Rufus will take care of the rest.
Step 9: In the next window, select the Write in ISO image mode (Recommended) option and click the OK button. If you see a warning for formatting the drive, simply select OK.
Step 10: Soon after, Rufus started creating USB boost. Depending on your USB drive, this may take some time to complete.
Step 11: Once completed, you will not see the message informing the end of the process, but you will hear the sound of the signal and the progress bar will turn completely green.
*Note:
If during the process you see the error message 'The image is too big for the selected target', that means your USB is lacking free space, not enough to hold the selected ISO file. Now need to find a larger USB or check the data inside it.
Need to copy data in USB before doing it.
Turn off all anti-virus software and firewalls so that they do not automatically delete the 'Autorun' file, causing errors and failing to create USB Boots.