Let's start with a very significant variable. Downhaul tension affects the overall luff curve of the sail, so it's important to get it right and balanced. How much downhaul tension do you need?

"If it's there's too much downhaul tension, you'll feel it in the water because the board will be flying a lot, the nose will be high, and it will be hard to control the board," underlines Antoine Albeau.

If that is happening, just release half a centimeter to see if it gets better. A small change can make a big difference. You'll notice the board will be "sitting" on the water. Also, if you don't have enough downhaul tension, the sail will feel heavier and overpowered, and the nose of the board will be diving in the water.

The same applies to the tack strap tension. More tension means more power in the sail. In flat waters, you can tight the strap because you're looking for power. In choppy conditions, it's always better to release it so that you can handle it well.

"For the boom height, it's better to have it higher in the light wind because you lie down more with the sail and have more control. In choppy conditions, lower the boom to get more control, more downhaul in the sail and more sitting in the harness".

With waist harnesses, go for short harness lines. You'll have more control, and it's easier to connect and disconnect from the lines. There are also specific masts for each type of sails. If you don't get the right mast, you'll feel that your sail will not behave well on the water.

"If your sail is too stiff, it will be hard to go fast and have control because the sail will be moving a lot. A softer sail will make you lose a lot of power", adds Albeau.

You have two eyelets on the sail - one in the bottom and one on the top. In Slalom windsurfing, you'll be using the bottom eyelet because you get more open leech, more speed, and the board will be freer. In light winds or upwind, you can use the top one.

"For the outhaul, it is always good to have an adjustable system on the boom because you can change the shape of the sail during sailing. I always leave the sail really full when I go downwind, and when I go upwind I tight it more to get less power," concludes Antoine Albeau

Finally, put more tension on the bottom battens because it will give the sail a right shape and stability.