Join Date: Jun 2005
Location: New Orleans
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Good advice above, especially from our Norwegian friend.
Most beginners leave the traveller in the middle, which is fine for the first few sails.
Later, you'll start moving it: to leeward if the breeze picks up, to keep the sail flat without bringing it too far in, so you don't heel too much.
Maybe a little to windward of center in light air, so you can ease the sheet and have a fuller main without letting the boom off to leeward too much.
The mainsheet and the traveller work in tandem. As a gross overgeneralization, when you ease one a little, you trim the other a little.