Consider the answer to this question: How many different axes of rotation can coexist?
Any rigid body, at any time, can only be rotating about one instantaneous axis of rotation.
Now, that said, if the body is asymmetric, like, say, a slab of wood, then you can think about spinning it quickly about its long axis and then more slowly about an axis orthogonal to that, but even then that's an illusion: at any given time, the block is undergoing an instantaneous rotation about a single axis, with the funky property that this axis will shift position with respect to both the body and the inertial laboratory frame.
My question is: if you have a 3D object that is no way symmetrical (not symmetric about the X, Y, or Z-axis) how many apparent, (if not actual), axis can the object be seen to be rotating around?
I suppose that is to assume that as the axis shifts "position with respect to the body of the object and the inertial laboratory frame" it will form a loop. the question is essential, how complicated can that loop be? How many different illusory axes can be incorporated?
My assumption is 3, maximum.