A return is simply a planet coming back to the degree it occupied at your birth. Saturn takes 29.5 years, so it returns at roughly 29, 58 and 87 — the traditional climacterics, and the reason the late twenties feel structurally different from the early twenties.
Jupiter returns every 11.9 years, at roughly 12, 24, 36, 48 and 60, and reads as expansion where Saturn reads as consolidation. Running the two cycles side by side gives a surprisingly legible map of when a life opened out and when it narrowed.
The lunar nodes return every 18.6 years — around 18.5, 37 and 56 — and describe direction rather than structure. Nodal returns often coincide with a change of what someone is aiming at, without any change to their circumstances.