One of the principal tribes of Europe, the Germans apparently had their origins in what is now Scandinavia. During the last two centuries before Christ, if not earlier, they settled in what is now Germany.
Most of the German tribes kept many large animals, primarily catttle (for meat and hides) and oxen (for ploughing and transport). When they moved, which might be every few decades during this period, they simply burned their wood dwellings and pilled their possessions onto large wagons pulled by oxen. Looking something like 19th century settlers crossing the American plains, the clans (each of dozens of wagons and hundreds of people) moved from their smoldering villages in the direction agreed upon by their tribal chiefs (male) and soothsayers (female). The movement would not be far, perhaps a hundred miles or less. In the year prior to such a movement small war parties had scouted out their destinations. Perhaps arrangements had been made with other tribes to move into territory nominally controlled by someone else. But there was plenty of empty land in Europe in those ages, or at least land that was easy to take from some weaker people..
Scouts on horseback and on foot went ahead of the wagon trains. If danger were encountered, the wagons were drawn into a circle and the men (and sometimes women) fought from inside the wagon circle. Depending on the lay of the land, the wagons would only make five or ten miles a day. Detours were sometimes neccessary to reach a ford in a river. The Germans were not bridge-builders like the Romans, but they could wield their axes to build rafts to ferry the wagons across water when a ford was not available. The actual movement would usually not take more than a month or so, for when the new territory was reached, preparations had to be made for Winter. The Germans were a tough bunch because they had to deal with the brutal (especially to the Romans) northern Winters. Since most German tribes originally came from Scandinavia or the Baltic coast, one could say that their constant migrations were simply an ongoing attempt to get away from the cold. The Romans taunted them on this point, and the Germans could not completely deny it.
Land was cleared by chopping down the trees and using them for homes and fortress walls. Oxen would be used to remove trunks. Settlements were preferably in valleys that already had been cleared. The Germans kept large numbers of domesticated animals. In addition to the cattle, oxen, and horses, there were goats, sheep, pigs, and chickens. And lots of dogs. Some crops would be planted, especially vegetables. If possible, a reserve of grain was carried on the journey to insure the tribe survived the coming Winter.
The Germans were a warrior people. Their principal weapon was the stabbing spear, not unlike the assegai of the Zulu, a people who in their heyday during the mid-19th century in many ways resemble the ancient Germans. Unlike the Zulu, however, or the Romans, the Germans were decent horsemen, and much in demand in Republican and Imperial times as cavalry. Although the German tribes had kings, these were less absolute monarchs than paramount chiefs, guys whom everyone more or less respected and deferred to, but who didn't really have to be obeyed. Wars were personal affairs. When the tribe decided for war, distinguished warriors would gather about them bands of men and go off to fight. This was one reason why the Germans tended to lose to the smaller, less numerous, and less ferocious Roman armies, which were much, much better organized.
But the Germans learned through long contact with the Romans. The many tribes --Goths , Vandals, Lombards , Franks , etc.-- which overran the Empire in its dying centuries were much more civilized than their ancestors had been at the time of Christ. Indeed, many of the German tribes were Christians and had a written language by the 5th century.
It was from the union of the German invaders with the Roman and Romanized populations which they found settled on the lands they had seized that the peoples of modern western Europe descend. And it was this merger of German and Roman culture which gave rise to the civilization of the Middle Ages in Europe.