You can draw various shapes in Excel using the drawing tools on the Drawing toolbar. You can draw everything from ellipses and rectangles to scribble shapes. Do as follows
1. Activate the worksheet you want to draw shapes in.
2. Click the toolbar button of your choice.
3. Draw at the bottom of the window (if you cannot see it you can right-click anywhere on a toolbar and click Draw).
4. The cursor becomes a black cross.
5. Hold the left mouse button and drag the shape to the size you want somewhere on the worksheet.
You can change line size, color, shadowing, fill pattern, etc. on the shapes you draw. Right-click the shape and select Format shape from the shortcut menu. Make the changes you want on the Colors and line tab.