If you're looking for directions for making a Foxtail chain and not the product called Foxtail, get the book, "Great Wire Jewelry: Projects and Techniques" by Irene From Peterson, Lark Books, Asheville, North Carolina. The Foxtail chain is listed on page 52.
If you haven't made chains before, you may find this one a little challenging--I suggest starting with colored wire (like copper and colored, coated copper) so you can keep the pattern straight visually. A caveat about this book: the gauge of the wire listed is a metric gauge that is not the same as the B&S gauge used by most suppliers in the U.S. For example, where the book lists 20 gauge, it expects wire at is 1.00 mm in diameter. This is more closely aligned with 18 gauge (B&S) wire you can buy from most suppliers.
Finally, you'll find that getting the links in the correct gauge with the correct inner diameter can be tricky. You're far better off making your own. There are any number of places you can find info on how to do this (Tim McCreight's book comes to mind), including the book listed above. The supplies you'll need include a jeweler's saw, blades (2/0 work fine), a bench pin, and beeswax or burr life--and the wire. If you're heavily into chainmaking, it makes sense to purchase a jump ringer (If not available here, then through a major silversmith supplier).