If you're looking for a quick way to view a summary of your sales, on a daily, and monthly basis, you can use the Members Area > Selling > Store Stats page, which provides you with a graph of your daily and monthly sales, for the past month and year respectively:

HipStamp: https://www.hipstamp.com/members/selling/stats
HipComic: https://www.hipcomic.com/members/selling/stats
HipPostcard: https://www.hippostcard.com/members/selling/stats

Quick Tip: To view the specific amount for any day or month, hover your mouse over the data points on the chart.

If you're looking for more comprehensive data regarding your sales, please see:
How do I calculate my fees & sales for the year?