Adjust twist and depth with sheet tension
The genoa trimmer's primary responsibility is to maintain optimal sail shape as wind velocity and other conditions change. More than any other control, sheet tension must be adjusted to preserve the same basic trim. The trimmer's secondary responsibility is to help the helmsman steer the boat. For example, he should ease the sheet for big waves or sudden lifts, and trim for flat spots and headers. Then, as the helmsman brings the boat back up to speed on the wind, the trimmer must slowly re-trim the sheet. All this requires constant communication. Trimming the sheet affects the genoa in several ways. It reduces twist and narrows the sheeting angle at the same time.
These changes combine to let you point higher. Easing the sheet has the opposite effect – more speed and less pointing ability. As a guide for proper sheet tension, observe how far the genoa is from the upper spreader and from the chainplates (be sure your spreaders are marked as described in Preparation). We cannot prescribe exact distances without knowing more about your boat and sailing conditions. These are measurements you'll have to get through trial and error.
» Set depth and twist with the fore-and-aft lead position