How to save up for a macbook and iphone?

I get 100 dollars a month for emergencies and food, stuff like that so id usually spend about half fter each month which means i have about 50$ after each month, I have 200$ saved right now. Macbook air is 899 which is the one i'm going for but i'm gonna buy it around aug 2015 cause i'm gonna need it for college and a new phone as well so that leaves me with about 10 months.

Get a job, do chores, cut neighbours grass, sell some of your possessions.