The 45-year-old, who was without a job following his departure from Asante Kotoko in December last year, joined the Accra-based club in a two-year deal this week as the club plans to avoid relegation.
“I want to work very hard to satisfy both the management and the supporters of the club,” Osei told Starr FM.
“Liberty Professionals have a great future as a club and I am going to work hard to achieve the needed results since it’s another challenge for me in my coaching career.
“We need to start picking valuable points to give us some breathing space in the league since our position is not the best. The real test begins now and we are prepared for it,” he added.
Liberty currently sit 11th position with 17 points, three points above safety. They have been able to pick just one victory in their last eight league games, scoring six goals and conceding seven in the process.
Osei will play his debut game this weekend when Liberty welcome city rivals Hearts of Oak to the Carl Reindolf Park in the Accra derby.