Try and keep active
You can often avoid seasickness by staying busy and keeping your mind occupied by taking over the helm or any other activity that will keep you above decks. Look at the distant horizon rather than the water close at hand. Take deep breaths and drink plenty of water. The worst thing that a person can do is go below decks with no land or horizon to look at. Reading or staring at an object will assuredly bring on the affects of seasickness.
If you are seasick and can’t bear it anymore, lie down on your back with your eyes closed. This will greatly reduce the affects.
If your eyes see what your ears are feeling, you have a better chance of avoiding seasickness