It's kind of hard to get in to the Christmas mood, when you live in country where they don't celebrate Christmas. At least in Dubai there was lots of holiday decorations, in Tunisia they only sell some decorations.
What i do, to get in the Christmas Mood:
Listen Christmas music
Watch Christmas movies
Put your Christmas Decorations (without decorations there's no Christmas)
Shop or make Christmas gifts
Drink hot chocolate and other Christmas related drinks
Make gingerbread cookies