I have 2 coat hooks screwed into the joists of my basement cieling about 4 or 4.5 feet apart.
I have 2 length of light rope with hooks in one end and 4 knots spaced evenly from the other end.
Hooks attach to the h-bars or stem in the front and the saddle, post or rack in the rear.
The distance between the hooks means the bike self centers between them.
The knots are used for easy height adjustment.
I know, I know.... If I were a welder, I'd be asking, "So where's the fun in that?"