The 19-year-old scored a fantastic goal as Feyenoord picked apart Go Ahead Eagles in a 5-1 victory this week.
The Ghana wide man faces Benfica in the Champions League on Wednesday night which will be his biggest test yet.
Osman said, “I have to make better choices more often. They say that at Brighton too.
“The people from the club watch, we discuss after matches what I did well but especially what I could have done better.”
Feyenoord coach Priske also commented: “One of the things for sure I would like to get into him is some maturity in his game. Knowing when to use his power and his pace and when to play one or two touches.
“Defensively also, when to find his right moments for pressure and how to go into pressure. He is really young but his speed definitely makes up for some things.”