Cala Tirant is the most reliable wave sailing location on the island, and offers a very different setup to most spots. There are various different areas that can be sailed. Depending on the day it can be fun but it can also be a demanding place to sail with big destructive waves. Tirant is sailed with winds from mistral (northwest) to gregal (northeast), which are very onshore winds. The big waves break far out away from the beach before reforming.
A nice long sandy beach and the best place to windsurf in a westerly. Can also work in mistral (NW) winds especially if there is a decent swell running, although the wind is gustier. The water is crystal clear (although sometimes there is sometimes weed in the water which can catch on your fin. If it is good you will probably find other windsurfers here and you may find kites although these tend to stay further upwind and there is room for everyone.
Port Addaia works with northerlies and is an interesting alternative to Fornells. The water is very flat which makes it a good spot for freestyle. On the days with strong tramontana (northerlies) a small wave wraps around the island and provides some good ramps, although water depth behind the island is limited. If you sail towards the outside island you'll find bigger waves although these can be dangerous and the rocks are sharp!
This beach can work with winds from southeast to southwest. Make use of the corners of the beach to get past the shorebreak and head somewhere else if it gets too big. There is a small sailing school that operates here during the summer months. All the usual tourist facilities can be found nearby.
Punta Prima can be a pretty good spot if you get it on the right day. Generally it needs winds with a reasonable amount of east in them, although it can also work on a southwesterly. Straight northerlies are too offshore and gusty, but strong Gregal (NE) can bring in decent waves and permit down-the-line riding conditions.The water is always clean and transparent which makes it a really nice place to sail.
The bay of Fornells offers a lot of space and security for windsurfers. The narrow entrance to the sea keeps the water state flat (although in strong Tramontana winds a half-metre sized chop can build). The bay can be sailed in almost all wind directions:
It can be sailed in northerlies which is sideshore. The rigging area is very pretty and protected from the wind. Getting off the beach the wind is very light and you might need to swim a bit but once off the beach the wind is constant. In the lee of the point you can sail in flat water or you can take the waves that form on the reef in the middle of the next bay down (S'Arenall de Morella).
Perhaps more of a surf spot than a windsurf spot but some days it works pretty well. Best on a not-too-big swell and especially worth a look in easterly winds. Winds with west in can be gusty as the wind comes over the small island which seperates Santa Tomas from Binigaus. The bar overlooking the beach - open during the summer months - is a nice place to relax between sessions.