Put the repair tape on the inside and stitch around the tear, as well as across it several times.
A bit of seam sealer will also help keep the edges of the tear from fraying.
Or, if you can find some matching taffeta at the fabric store, you could make your own patch with seam glue?
Either way you'll need to stitch around the patch to keep it on, so it won't be completely invisible. But if you wanted perfect you wouldn't have bought the jacket to begin with, right?