The basics of tuning your Standing Riggings
Start by tighten the forestay and backstay shrouds and lowers until they are snug but not tight. Now tighten the forestay and backstay till the roller furler doesn't sag but rotates easily . Now to make sure the mast is not leaning to either side of the boat. You can measure this with the main halyard. Release the main halyard so that it just touches the toe rail on one side, secure the halyard, and then check the other side. Adjust the upper shrouds until both measurements are the same. Add a full turn to each shroud turnbuckle to snug. Sight up the grove in the mast to see if there is a bend or curve in the mast. Adjust the lowers until the mast is straight. Now go sailing. While sailing keep an eye on the leeward side shrouds. They should be at rest but not slack. Start with the upper shrouds and remove the sloppiness equally. Don't try to remove all the looseness in one go but a little each tack till they are all tighten. Adjust them on the lee side after you tack and they become slack. This is to take out the whipping that would occur as you load each side while tacking. That whipping action while the mast is unsupported to each side will stress the rigging as a shock load. Now adjust the lowers shrouds starting with the forward set lee side then tack, adjust lee side moving back to the next. Again I must stress the point Don't try to remove all the looseness in one go but a little each tack till they are all tighten. If you start to see a bend in the mast loosen off and start over don't try to tighten one side to remove the bend. When you are finished the shrouds should be "At rest" meaning no tension and no sloppiness if you're heeling. Boats that sail in heaver winds or carry more sail will have more tension on the running rigging. While sailing release the helm The boat should round to weather (into the wind) if you find that you are fighting the helm to keep the boat on course you may have to much weather helm or worse lee helm. Weather helm can be added by adjusting the sails, generally by spilling wind off the main. If you have to spill too much air to the point that boat speed suffers greatly you might need to reduce the rake in the mast. If the mast is raked forward than you will introduce "lee helm" and the boat will try to jib. Rake the mast aft you will introduce "weather Helm". This is only the basic tuning adding for racing as putting a bend in the mast top and or for sail shape requires further adjustments and consultation with the rigger and sail maker..