Easy, lead the turn on to the arc by 10 percent of your ground speed.( Eg. GS 250 kts, start the turn 2.5 miles prior to the arc.) If you have an RMI and DME it's a piece of cake. Put the RMI needle at 90 degrees off you nose (zero wind) and just bracket the DME.
On the localizer back course, you "become" the localizer needle. If it's off to the right of center, turn left to join the loc.
hope that helps.
fbh