There are several techniques I use for such situations.
1. Set the camera to maximum resolution and then use wider lens thus increasing shutter speed, then crop on computer. (better to have grainier pic then blurr one. If need faster speed, increase ISO)
2. One trick I like to use, also, is to press the camera snugly against my face with the camera strap (neck more steady than hands

), then lean on any available support like wall or lamp post (if possible, I hold the camera steady on the support), or even sit with knees propped supporting my elbows.
3. If I remember to bring along, I will use my trusty beanbag which I bought in London. this one can place your camera on any uneven shaped support, like rock, then using hand pump to remove air until the bag is rock hard.