ok found it (had it on my iPhone)

Grab a spray bottle from the cheap shop (also grab a travel sized one to carry with the mat if you wish).

For a travel sized container use:
1 cup of distilled water
vinegar or witch-hazel (optional)
Tea tree oil
Eucalyptus oil (or lavender)

Use a 2:1 ratio for the tea tree/eucalyptus - I use the cheap double d stuff from the supermarket. Approx 10 drops of Tea Tree to 5 drops of Eucalyptus. Both of these are antibacterial oils.

Either saturate your mat & let it air dry (great to do at home), or spray the mat and wipe it down (great after a sweaty class).

I'm out of mine, will have to make some more for the mat at home, plus for when I get my new mat in a couple of weeks time.