So, even though typical clouds do contain a lot of water, this water is spread out for miles in the form of tiny water droplets or crystals, which are so small that the effect of gravity on them is negligible. Thus, from our vantage on the ground, clouds seem to float in the sky.
In respect to this, what keeps a cloud together?
Because they are so small they are easily kept up by the rising air. So the reason that clouds can hold water droplets is because the air in clouds is rising, and the rising air keeps pushing the water droplets up. Basically, it's the same with snow, but a cloud holding snow or ice crystals must be colder.
How do clouds go away?
Virtually all types of clouds and precipitation are due to rising air. On the other hand, as air sinks, its temperature rises and its capacity for holding vapor increases. Then any cloud droplets tend to evaporate and the cloud itself disappears; evaporation changes moisture back from liquid into gas.
Why do clouds stick together?
These airborne water molecules are called water vapor. When the molecules are bouncing around in the atmosphere, they don't normally stick together. Clouds on Earth form when warm air rises and its pressure is reduced. The air expands and cools, and clouds form as the temperature drops below the dew point.