You can also get a feel for the steadiness of your stance.
Take your telephoto and practice shooting outside at a distant object with your telephoto at 300mm. Using shutter priority, start at 1/250 of a second (close to inverse of the focal length) and take a photo. Now take a few more for practice at 1/500, 1/125, 1/60th. Examine your photos to see at what shutter speed is the photo acceptably sharp. Try it again with your tripod as a monopod (one leg extended). Every person is different.... My cousin can handhold a couple stops slower than I. I'm about 1/focal length + a little more. If I'm really careful, I can probably do 1 stop slower. It takes practice...
* breath through your shots
* Feet spread apart at shoulder lengths
* Don't run around trying to get into position (if possible). keep heart rate and breathing calm.