After your form is created, you'll be placed immediately into Layout View, where you can change the arrangement of your form. If, for some reason, you're not in Layout View, choose it from the drop-down box underneath the Office button.
From this view, you'll have access to the Form Layout Tools section of the Ribbon. Choose the Format tab and you'll see the icons shown in the image above.
While in Layout View, you can rearrange fields on your form by dragging and dropping them to their desired location. If you want to completely remove a field, right-click on it and choose the Delete menu item.
Explore the icons on the Arrange tab and experiment with the various layout options. When you're done, move on to the next step.