Next thing is to use the tripod properly. Always use the lowest possible position you can get into, so sitting or laying down is the way to go. This has two reason: first of all, it’s more comfortable, but more importantly, the lower the tripod is the more stable it will be.
For the same reason, when setting up the height of the tripod, use the legs, not the center post, as three legs are more stable than one. If possible, try not to touch your tripod or glasses. Point them at something, adjust the focus, and leave them. A finger on the focus wheel or your head touching the eye piece will result in small vibrations, especially when we’re talking big power spotters.