- watch a film (rent/borrow a DVD / cinema)
- read a book
- invite a friend home and cook dinner for him
- go for a small walk before sleeping
- write a long mail/letter to your family/friends back home
- invite friends home to play a game / cards
- have a relaxing bath/shower and drink a tea with camomile
- decide to learn something new (language, drawing, computer program...) you can find so many things to learn on internet

Good Luck :-)

PS: if nothing works try relaxation/meditation music (from internet on You tube and others..)