How did the first UFO look like?

At night a UFO should be able to perform movements that normal planes cannot. such as zig zag or several objects merge or a craft "turning on a dim". Possibly be so light like a bright star but change a number of colours as it "powers up" with the plamsa corona that you may be able to see it just as it shots off.

In daylight a UFO would leave no trail or exaust and perform movements not possible or speeds unlike normal planes.