Ok so now a days this is NOT something we would be doing because of the chemicals in the soil and modern means to do it better. But if this was times of trouble and you need a water source this can be part of the plan.
A dowsing rod, (pdf on how to dowse) a shove and a pick are what the people of years past use to use. They would dig the well anywhere from 6 to 100 feet deep depending on their location. Now the water in the well was not necessarily a hit to a water source, but seepage through the ground of surface water.
Basically start digging a hole the size you want your well to be. At least 4ft wide and deep, again depends on rain fall in your area and drainage in the spot you are digging. As you dig down you would need to line it with stone to prevent cave in's (now a days we have brick and other stone items we would be able to salvage to do this with to). As you go deeper make sure to have a rope on the digger to be able to pull them out if collapse happens. The deeper you go the less chance of dry up during the warmer seasons.
A roof was built over the well to help prevent debris from falling in and contaminating the water. Usually a crank assembly and bucket were built into the roof to provide a simple means of removing the water.
Another pdf - How to dig and care for your well Click here
Side note: Many people had more than one well in different locations in case one dried up.
And the song for this post has to be
Maroon 5 - Come Away To The Water (not really on topic, but it is a pretty song)
ok I know most already read the blog but got a comment that I should of posted this song
so here it is!! It is a good one.