With respect to you, JayLenochiniMac, you seem to be making this up as you go along and you are wrong. WatchOS 3 is installable without a dev account (I've just done it). It just requires a more specific sequence to be successful.
Here's the steps. Join at whatever point is appropriate for you (i.e. if you've already upgraded to iOS 10 don't try to do so again)
1) Upgrade to iOS 10
2) Reset Apple Watch
3) Pair Apple Watch and do not restore backup (and I'll be honest about my shortcomings here and say I have not tried restoring, but I don't expect it be successful. If you restore and the instructions still work please let the community know
)
4) Install WatchOS 3 Beta Profile to watch. Installing to iPhone does no harm but it does no good either
5) Check for Software Update and install WatchOS 3 Beta
6) Enjoy. But it ff it breaks you get to keep both halves
Hope this helps