Try not to use footnotes.

Asterisks and the footnotes that go with them slow readers down. You’re interrupting their train of thought and asking them to hunt for secondary information.

If you need to use footnotes, insert a number formatted in superscript at the end of the sentence. Corresponding footnotes live at the bottom of the page or screen.

If you need to cite legal copy, use footnotes when you’re citing more than one thing on the page. Don’t put the footnote in the middle of the sentence. Put it at the end instead. And don’t use multiple footnotes in one sentence.

Examples

The #1 iPad POS—QuickBooks Point of Sale.¹ Clear business data anytime.²

Revel Systems was ranked #1 in Top Ten Reviews: http://pos-systems-review.toptenreviews.com/ipad/revel-systems-review.html
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