Holding up the front with a normal stand is easy enough. If you really need the back lifted as well, maybe put a box under the frame?

For me it's fine to rest the rear on the floor, when I remove the wheel. Could put a towel or any other padding under it. Or use a rope to pull it up from somewhere.
For an easy homebrew you probably just need 2~3 hooks to hang ropes that are tied in the area the bottom bracket, the handlebars and the headrest.

Put the hooks into the walls and ceiling or on your existing garage furniture or build a simple wooden frame for that. This will of course not be very rigid, but free to swing around.