The Three Lions will play the world champions at Signal Iduna Park on Wednesday in what will be Southgate's first match in charge since being confirmed as full-time coach following Sam Allardyce’s departure.
Southgate outlined his long-term plans for England to the players at St George's Park on Monday.
"It's the first opportunity I have had to work with the team, with the knowledge that there's a longer term plan," Southgate told reporters.
"So, I think it was important for the players to have an understanding of what drives me, the type of standards that I think we have to set, what's possible but also the reality of where we are.
"That's not just this group of players, but as a country over the last few years.
"We have to change how we do things - we have to change the way we think, we have to change the way we work - because we have not had the same success that our opponents have had over such a consistent period of time.
"So, in that respect, they [Germany] are a great model for us to look at,” he added.
“We are not looking to copy anybody, but you have to respect the way they have continually reached semi-finals, finals and won things. That's the mentality we have to have."
Southgate also confirmed that Chelsea’s Gary Cahill will lead the team against Germany, with regular captain Wayne Rooney not in the squad.
Cahill will miss Sunday's World Cup Qualifier against Lithuania through suspension.
England are undefeated under Southgate and are hoping to record successive wins over Germany for the first time in over 80 years having defeated Joachim Low’s side 3-2 in a friendly last March.