How do I return to worksheet from chart?

How do I return to worksheet from chart?

I'm not sure where to look for help on this. I've entered a worksheet, and created a chart. After looking at the chart, I'd like to make some changes to the worksheet, and change the format of the chart. When I load the worksheet from the sidebar, the chart opens up on top of it, and I can't see the cells to do data entry. Where should I go from here?