Chris, IMHO sales go down on summer. Europe and U.S. are responsible for a vast amount of sales and people definitely tend to stay out of home for more time on that warmer period of the year.
I think that there are several ways to keep your cashflow healthy though. Investing on your business on that part of the year is very important. New Designs, New Content Management Systems...
Innovation needs to be there all the time, but in my eyes, summer should be the time of the year adult business men and women work harder than ever.
Just don´t get too stressed out or...
Take care,
Bruno Dickman