Symptoms:
Blisters (fluid filled whitish) on hands, feet, mouth and sometimes nappy area. Sometimes on all areas, sometimes only some.
General unwellness - runny nose, bit off.

That's basically it.

It's viral so there is no treatment that I know of, just runs it's course. It is very contageous in the blister stage - don't pop them as it is the fluid that passes the virus on.
It is easily passed via mouthing - one child mouths something that another then does the same to. Shopping trolley handles are a good example.