The 0-360 bezel is basically a mnemonic to help you remember the wind direction. Set it so the wind direction is at the top, and the other markers will make some sense: "Windward Leg" at the top SHOULD point straight up the leg (but usually doesn't in the real world!
"Starboard Tack Angle" and "Port Tack Angle" each give you a couple of marks, either because some boats (and skippers!) point higher than others, or to show you lifted and headed angles. They're seem to range from around 34 degrees off the wind down to around 45.
The "+/-" marks at 3:00 and 9:00 are (I think) just to remind you that lifts are towards windward and headers aren't.
"Starboard Reach" and "Port Reach" are to give you an idea of where a reasonable angle might be for "tacking downwind".
And "Running" shows a small range of angles around dead downwind.
I'm taking those marks from my Citizen Navisail "Stars & Stripes" model (the older one, without the solar cell), and I'm using a magnifying glass, because there's no way I can see that type with my normal glasses!
I race sailboats (15' Albacores) constantly, and I have NEVER used that bezel during a race, mostly because my Suunto tactical compass gives me all that information, and more, and clearer and better.
In fact, I've completely stopped using my Navisail watch in races, because its most amazing feature -- the complex beeps that tell you exactly how much time is left before the start, 5 for 50 seconds, 4 for 40, etc. -- is pretty useless when the wind is above maybe 8 knots, because I usually can't hear it. So I've switched to some Casio watches that beep dumber but louder. (And I'm shopping for a Ronstan that I'll be able to read without hardly even looking!)
I still love my Citizen watch, but I only wear it on shore! I do wish it had a backlight and an hourly chime, both of which are missing. But it's still a gorgeous and impressive watch. I've even had a couple of jewelers stop me and ask to look it over!
Norm in Toronto