Sometimes it's just not possible to avoid using the tripod altogether. Especially with landscape photos during the 'magic hours' (dawn or dusk), tripod is almost a define must. It will be worth the extra weight.
Other than watching your physical posture and using impromptu supports, you can try bumping up the ISO, and if you're using a DSLR, get IS and/or fast lenses.
there are techniques to help u keep your hands steady, such as your posture, keeping hands locked, holding your breath, finding something to support on, etc. settings-wise, keeping a fast shutter, of which may require using bigger aperture, higher ISO. focal length will also affect. more tele means any slight movement will be magnified, so the wider the focal length, the less the effects of any camera shake. got some cameras/lenses come with vibration reduction(sorry i nikon user) or the like, means the equipment got the technology to reduce camera shake to a certain extent.
If no tripod and must use a tripod, u can always rest yr camera on top of stone, bench, dustbin, car roof, then use the 2s/10s timer to trigger. I have tried all these, it looks weird and unglam, but u will get the shot.