To repeat a section of a chart, start and end the section with repeat brackets |: - :| or { - }. You'll find them in the symbols tumblers below the standard bar-signs.
The repeat brackets will cause the bars within to repeat once. Using text (placed anywhere between the brackets)
you can tell the player to repeat more than once.
x3, x4, x5, etc. in fact those choices are available at the bottom of the text selection tumbler that you can see if you touch the icon displayed to the left of the text input field. (These tips are based on my iPod Touch experience)
)BOB