Anywhere from every other day to every few days is fine. It is really not a biggie, you're just trying to avoid both long periods of abstain and many days of release in a row.
Yes that's right - doing regular release with the one attempt is much better chances of conception than either abstain or FR, and since you're still doing the one attempt (which actually sways, unlike abstain/FR which have appeared to do nothing whatsoever) you get all the benefits without the drawbacks, if that makes sense.