The Union Soldier....
When the war began, the United States had only a tiny paid army. States had volunteer militias to help the regular army. The need for more men became greater. Both sides started a draft or conscription. The South started it in 1862. The North started their draft in 1863. Thousands of men from Germany, Ireland, France, Spain, England, and Italy were in the Union army.
"A House Divided" refers to the Civil War. Brothers fought against brothers. Fathers fought against sons. Daughters were separated from their parents. Both Abe Lincoln and Jefferson Davis, the Confederate President, had in-laws fighting in opposing armies. Two sons of Senator John J. Crittenden made Major-General, one was in the Union Army and one was in the Confederate Army. The United States' Attorney General Edward Bates had a Rebel son. General Robert E. Lee's nephew joined the Union side.
Most of the camps were not clean. If there was a stream , the men tried to bathe and wash their clothes. Drinking water was dirty. Many men died of disease. It is estimated that for every one man who died in battle three died from disease. Army rations were usually hardtack, coffee, and salt pork. Hardtack was called "teeth dullers". It was 3 and 1/2 inch square of baked flour, water and salt. When marching, hardtack was placed in the cheek to mix with saliva. Fresh fruits and vegetables were hard to come by in the camps. This caused scurvy. Stonewall Jackson was fond of sucking lemons. Men were told to look for wild onions to eat. Both the lemons and onions helped to prevent scurvy.
A Union soldier was given a canvas of about 5 feet by 5 feet for his tent. To use his tent, he needed another soldier. The two men would put up 2 forked sticks and button their canvases together in the middle. They would stretch the material over the sticks. Many times, their feet stuck out of their tents when they laid down to sleep. Rain came in both ends. Barrels used to store food was turned upside down to serve as tables or chairs. The bathroom was a hole dug several yards away from the shelter.
Life in camp was not real exciting. Private Oliver Norton of the 83rd PA writes that the first thing in the morning was drill, drill, drill, and drill. In between drills, the soldiers were assigned to protecting the camp, building roads, digging trenches for bathrooms, caring for horses and mules, repairing equipment, looking for firewood, and keeping their weapons clean.
During the Civil War, the soldiers marched in long narrow columns. Once on the battlefield, the column changed. Men lined up to face the enemy. During battle, the men would move together following orders shouted by their officers.
Long hours of training on a drill field was needed before maneuvering on the battlefield. They trained in all types of weather and wherever they could practice. Soldiers didn’t like the drilling. They wanted to fight and not spend hours practicing. It was difficult for some of the men to take orders from a stranger which made drilling all the more important.

The official Northern army uniform was blue, but many regiments choose their own uniforms. A famous NY company of volunteers wore baggy red pants and short red jackets. The Iron Brigade of Michigan wore wide-brimmed black hats with a feather curling up the side. Union sharp shooters wore dark green uniforms, leather leggings, and feathers in their hats. This was an attempt at camouflage.

The Confederate Soldier.....

Southern armies seemed to be more disciplined and more relaxed. The South had most of the experienced officers and soldiers at the start of the war. Drilling was kept to a minimum and saluting, saying "yes sir" , "no sir", and keeping an neat tent were not enforced. At the beginning of the war, many units had as little as 3 weeks of training before going to battle. At times, the boys went from schoolroom to battlefield.

The Confederates didn’t have factories to make uniforms. The Southern women learned from neighbors and grandmothers how to weave cloth. The dye often came from butternuts. The "Confederate Gray" became warm brown from the butternut dye.
At the beginning of the war, some confederate soldiers, Abel Sheeks was one, wrote about searching dead men to find a uniform. "In just a few weeks my uniform was equal of anyone's.