After SignIn in Google Analytics, you reach at Dashboard first. At right corner you see a date range of one month like this image, it a calender to select the date.
This is drop down calender, you can select date for a particular date and also for a range of date like for one week or one months according to your requirement. If you will see below image, notice dark spots in middle, is a selected range for one month stats.
After selection of date click on Apply Range Button, wait for a while, you will get a traffic report described throught graph and other elements.