What's the best (simplest, most reliable) way to make a system backup?

I tried Backupper but when I wanted to Restore it said: Image file doesn't exist.
When I found the image file myself, it said: You should have backed first (when I thought the image was a backup)
After that it said: You should be running (something) from flash drive.

It just got too stupid. It informed me of all the things I should have done afterwards! It also took 3 hrs to image a disk and then told me there wasn't enough space.

I don't want anything that requires that a Restore is done by the same version as the one that created the image. I might have upgraded since then.

Is there something foolproof, I'm a pretty good fool!

Thanks - rev