How daily life looked like in the camp depends heavily on what the prisoner's in question job was and to a certain extent the point in time.

I will forego the early camps because they were less organized and try to answer the question concerning the established concentration camp after 1934 system since I think that is what you are asking about.

In broad strokes a day in the camp started with a wake-up call, followed by very limited "wash" time (i.e. being able to get some water on your face) and then latrine time; then came breakfast consisting of a slice of bread and brown water that was supposed to be coffee (one recurring theme here in survivors' testimonies is that you didn't want to be first in line as to get some of the "coffee" grind in your cup so that you would have something solid to eat), then came roll call where every prisoners of the camp assembled at the parade ground of the camp to be counted; then the work details left for their 8 to 12 hour work day at their assigned work places; if something akin to lunch was served, it was consumed at the work place; after work the work details returned to camp, were counted again and then another meal consisting of a slice of bread and thin soup was served; and then the people returned to their barracks.

As I said, your daily routine as a prisoner depended on which job you had, some offering more freedom like working as a clerk in the camp administration or the sick barracks. Some work even entailed a day-off while other had to work seven days a week for hours straight. Privileged jobs were most often given to German prisoners who had been sent to the camp as political or criminal prisoners while Jews were generally not offered any privileged jobs. The most coveted jobs were those in the camp kitchen because they guaranteed that you would be able to eat some extra food and the jobs at "Canada", i.e. the depot where the possessions of prisoners were kept because that made it easy to gain access to stuff to trade for food etc.

The whole idea of organizing camp life like this came in the early 30s with the Dachau model established by Theodor Eicke, the first commander of Dachau and first Inspector of the Concentration Camps. After the early camps run by the SA came into the crossfire of critique by the established authorities like the police and the justice system and the ministry of justice threatened to take over the prisoners into the regular prison system, Eicke organized the camps as to give them a more military flair in order to fend off accusations of chaos and arbistrariness. The system was refined over the years but in its essence kept and included the military routine, the prisoner uniforms and so and so forth. Its most heinous addition came in the form of integrating the prisoners into the administration of the camps thus creating such figures ad the Kapo and prison doctors, jobs that made it easier to survive for prisoners but also included some form of compliance.

Sources:

• Nicholaus Wachsmann: KL. A history of the Nazi Concentration Camps, 2015.

• Laurence Rees: Auschwitz. A new History.

• Karin Orth: Das System der nationalsozialistischen Konzentrationslager. Eine politische Organisationsgeschichte. Hamburger Edition, Hamburg 1999.

• Various survivor memoires, primary among them those of Primo Levi and Hermann Langbein.