A couple more stability tricks:

Tie a rock or other heavy-ish object to a string, so it hangs most of the way to the ground. It helps absorb vibration, and the long radius slows wobble. A long stick works (like a short monopod), but is more bulk.

Another string trick is to use a heavier string, such as paracord or other thick twine, and let it trail much longer from the monocular (in this case, at least -- people use both of these with binoculars and cameras). The string MUST trail on the ground. Step on the string, and pull it tight, upwards with the monocular, while viewing. This isn't so great for tracking from a higher to a lower field of view or object, however, as there's not a great way to keep taking up slack.