You may need to rotate contents to have the best fit your work, especially when working with a chart where the horizontal axis has long names. Please follow the steps below to rotate the content up:
Step 1: Select the contents you need to rotate, in this example, the x-axis;
Step 2: Click the "Home" Tab from Ribbon;
Step 3: Click the small triangle after orientation command, then select "Rotate Text Up";
Step 4: The selected contents will rotate.