The wideman, who had his medical on Wednesday evening and will spend the coming campaign at Goodison Park, described the move as a "dream".
"I'm very happy to be joining Everton because it's a great club, which likes to play football, and it's a great pleasure to be here," the 22-year-old told the club's official website.
"Playing in the Premier League has always been a dream for me and I have achieved that dream.
"This is the biggest level for me to play at. I know that it's a very competitive league and I believe with hard work we're going to be successful this season."