Set up the browser extension
Five steps, about two minutes. Upwind isn't in the Chrome Web Store yet, so this installs it the same way any early-access extension does — by pointing Chrome at the files directly. Nothing to be nervous about; you can remove it just as easily later.
Download the extension
Unzip it
Double-click the downloaded file. You should end up with a folder named yacht-crew-apply-extension — leave it somewhere you won't delete or move (e.g. your Documents folder), since Chrome reads the extension from that folder every time it starts.
Open Chrome's extensions page
Type chrome://extensions into the address bar and hit enter.
Turn on Developer mode
There's a toggle for it in the top-right corner of that page. Switch it on — new buttons will appear.
Click "Load unpacked"
Select the yacht-crew-apply-extension folder you unzipped in step 2. Upwind will appear in your extensions list — that's it, done.
That's it — no token to copy
Go back to your Upwind dashboard's Account tab and click Generate new token — it applies itself to the extension automatically as long as the extension is installed and Chrome is open.
If something changes and it stops working
Every so often the extension gets updated. There's a Reload extension button on the Account tab that picks up updates automatically — you only ever need to manually redo the steps above if you moved or deleted the folder from step 2.