I have been a lead pilot several times over the years and offer the following.........
+++ 2 place flight with student is an excellent first step. Student fly the same route, solo the next day.
+++ do it on good soaring days with low wind.
+++ if flying with a lead pilot, launch together with instructor first.
+++ use different frequencies.
+++ instructor be willing to pull spoilers and go down to save student......"get right on my tail and do everything I do".
+++ stay loose, as it has the potential to become a very disorganized cluster-f***
Have fun,
JJ