If the holes aren't too big and not too many, go to a sailboat store or westmarine and get a roll of sail clotch patches.
Its like a sticker, with some glue one side. Put one on each side of hole.
I used to do that, but before just applied a little 2 component glue such as Araldite on the hole, to prevent further tear.
It lasted for years....again, depends on the hole sizes and quantity.
Still have a sail from 1985 with those!!!
If you are handy, you can also stitch patches, I did all by hand stitching when I was younger....can't see now....