I've been trying to create a bootable usb of windows 7 setup to do a clean installation on my laptop.I have a 32 GB Sandisk USB (3.0) and my hard drive is GPT. At first, I used Rufus in MBR partition scheme and selected target device as UEFI(CSM) because my UEFI device has support for legeacy bios ( I saw the option in my UEFI settings.) But everytime I tried to boot from the usb, it kept showing no media present. I thought rufus formatting my usb as ntfs was the problem( fat32 oprion was unavailable ). But when I tried making the bootable usb with YUMI with FAT32 selected, it said not enough disk space in the middle of the proccess(where 7zip extracts the files to the usb). I think it's because my iso is too large(over 5 GB). So in this situation, what do i have to do to successfully make working bootable usb of windows 7 ?
fat32 option was unavailable
my iso is too large (over 5 GB)
Then it looks like you are not using an official Microsoft Windows 7 retail ISO. If you did, then your ISO would be smaller than 4 GB, and, when creating a drive for UEFI boot, Rufus would also allow you to select FAT32 as the file system.
I'm afraid that, because there is no way to tell how your unofficial ISO might have been altered, possibly in ways that completely break USB boot, you're probably not going to get much help here.
I would therefore encourage you to get your hands on an official Microsoft Windows 7 retail ISO, and see if that works better.