There is daily bus connection between Paphos and Nicosia. The ticket prices is € 7,00 for a single trip and € 13,00 for day ticket (which you can use for a return trip in the same day). More information about the tickets visit Intercity Bus Tickets. The trip duration about 2 hours and depends on the traffic. In the morning hours (7-9) there is traffic at the entrance of Nicosia.

Departure time from Karavella bus station, Paphos
Monday to Friday: 05:30, 07:00, 08:00, 09:30, 12:00, 14:30, 16:30, 18:30
Saturday, Sunday and public holidays: 08:00, 09:30, 15:30, 16:30, 17:30
The route: Karavella bus station (starting point - Paphos), District Court, Toyota dealership, Pafiako stadium (opposite Debenhams), Kianos Stavros (oppossite McDonalds Pafos),
New Nicosia Hospital, 'Kalispera' Traffic Lights, Apoel (Nicosia), Ministry of Commerce, Cafe Sitio, Solomou Square (Nicosia).
Departure time from Solomou Square, Nicosia
Monday to Friday: 05:00, 06:00, 08:00, 12:00, 15:00, 16:00, 19:00
Saturday and Sunday and public holidays: 08:00, 10:30, 14:00, 16:00, 18:30
The route: Solomou Square, Cafe Sitio, Apoel, Ministry of Commerce, Apoel (Nicosia), 'Kalispera' Traffic Lights, New Nicosia Hospital,
Kianos Stavros (oppossite McDonalds Pafos), Pafiako stadium (opposite Debenhams), Toyota dealership, Paphos District Court, Karavella bus station.
Notes
* Wednesday only
** Except Wednesday
*** Stops at Neapolis University