To resize a portlet's height without accessing portlet configuration, do the following:
Rest your pointer over the bottom edge of the portlet.
Click and drag the portlet to the proper height. The new height is saved automatically.
Tip:
If there is a gap between the current portlet and the portlet below it, double-click the bottom edge of the current portlet (the click-and-drag handle) to automatically increase its height to fill the gap.