uefi – Best practice for getting Lubuntu installed on Dell E5470 laptop (Boot Problems)

I see many posts related to boot issues and legacy vs secure boot, etc. My goal is to clean install Lubuntu from a bootable USB stick. So far, every combination I have tried (legacy boot mode, UEFI boot mode, secure boot on/off, etc) has not resulted in a bootable lubuntu install.

Setup goes fine. I choose the option to erase the disk and it configures an ext4 partition and copies all the files fine. At the end when I reboot, I either get a blank screen forever, or I get the restart and then a “No valid boot device” type error.

I am willing and able to start again from scratch with the usb stick. I would just like to know the 100% best way to have the BIOS settting configured before I start?

Is there a FAQ or best practices article that will help me get things right from the start?