The 20-year-old is hoping his hugely successful loan stint with Watford will rub off on his return to Teesside.
He told the Evening Gazette: "It's been absolutely brilliant at Watford. I can't thank them enough for giving me that chance.
"They played me week in and week out and I got a few goals and assists.
"I thought I might have stayed there, but the gaffer said that he wanted me to come back here and do what I can for the squad.
"The Premiership is the place to be and I can't wait to get started again."
At the same time, Johnson is not fooling himself that the task of breaking into the Boro line-up will be any easier.
Johnson said: "We've got regular players on both wings but I just have to get my head down and wait for my chance.
"I don't mind at all which side I play on. You see all the best players in the world cut inside, but then I have always practised with my right foot and it's not too bad now.
"The one thing I got from my time at Watford was confidence. I've always been a confident player, but I have never played three games in a row for Boro and until you are playing regularly you don't settle down and show what you can do.
"But my chance will come if I keep on doing the right things."