First of all, travel with someone more observant than you, like my wife.
Walk quietly until she points out the Ermine to you, mere feet away.
Avoid crowds of screaming children.
As the Ermine starts to flee "squeak", its curiousity will get the better of it and it will come to try and choose you. Keep it up as it pops in and out of rocks, at times appearing right at your feet.
The "kind of" part, hand holding a camera at slow shutter speeds will probably result in fuzzy images. Full on camera mounted flash will not save you as the eye shine makes it look like full on, camera mounted, flash was used. When you do get a flash shot that doesn't blast out the eye shine, focus on the wrong part of the animal so the eyes and face are not sharp.
Keep taking the photos until said crowd of screaming childrens show up to see what you're taking pictures of.
Keep your best couple of images, cursing their lack of sharpness and hope people only look at them at low resolution. Like this...