GMT hours of the different forex trading session.

Sydney session : Open 9 PM Close 6 AM
Tokyo session : Open 11 PM Close 8 AM
London session : Open 7 AM Close 4 PM
New York session : Open 12 AM Close 9 PM

If GMT+1 :

Sydney session : Open 10 PM Close 7 AM
Tokyo session : Open 12 PM Close 9 AM
London session : Open 8 AM Close 5 PM
New York session : Open 1 PM Close 10 PM

If GMT+2 :

Sydney session : Open 11 PM Close 8 AM
Tokyo session : Open 1 AM Close 10 AM
London session : Open 9 AM Close 6 PM
New York session : Open 2 PM Close 11 PM

Etc...