Consider two RAF chains:
A > B > C
A > D > E

Boost BCDE, with A.
You'll get a free toon on A, for every set you boost (from granted levels).

If you don't have a booster, make your first set... 5x whatever.
With a toon that can boost on the 'A' account.
Both 5x Druids or 5x Paladins would be a great first set, as they can Dungeon Finder the whole way up... and either a Druid or Paladin makes a great booster for later sets.

For every four sets you boost (on BCDE) with A...
You end up with:
A Booster + Six Toons from granted levels.
B/D Four boosted Toons + Two Toons from granted levels
C/E Four boosted Toons.

Basically C gives two toons to B (as does E to D).
And that allows B & D, to each give an extra toon to A.
(Granted levels received, count as levels gained, which allows you to grant additional levels based on those to the referring account... Cascading granted levels).