Right - I've just been out to try to take a photo of how to carry a bike...
Headtube/toptube join resting on shoulder. Back wheel forwards and down. Hand holding chainstay to stabilise & take the weight over bumps to reduce shoulder bruising - that's how I do it.
While I was out there, I experimented riding two bikes at a time round the grounds of Wobbly Towers.
I found it much easier than I remembered. Riding the allotment MTB while pushing the fixie was easy - tight turns, 'trackstands' using bike No.2 as a walking stick.
In fact I found it easier starting from one of these 'trackstands'.
Further experimentation proved that using the Wobblebike as bike No.1 is perfectly feasible, but Wobblebike as bike No.2 was probably not a good idea.
Difficult to get proof with only 10 secs of self timer on the camera, but here's a photo taken while on the Wobblebike
(Yes, camera in one hand, bike No. 2 in other hand and both feet on the pedals).