Ill start off by saying, dont play shaman hunter, get a ret instead, but if you want to try this shitty combo too, here are shaman POV tactics.
Warr/Pally - In this game if the warrior goes on the shaman, then you have to cancel cast on every overpower ofc to not get UA, but it is sometimes easier than when they are on your hunter, you basically tank him, until you have cc for the pala, the warrior will charge your hunter, switch to shield and absorb allot of damage, when they are on you dont forget to keep purging all the time : ) - also dont be afraid to use BL deffensivley. You should be constantly shocking the pala, if your not using it on pretty much every CD something is up, and while sacred shield is up the warriors health wont dip, if its ever on while the pala is in cc, or your hunter has distance, then you are fucked. As a shaman you should also try to weave your hex's in (download gladimish to track your cc DR's), i tend to use them as an interrupt after wind shear, say you shock a FoL then he casts a Holy Light, you can hex it, creating great pressure. Use Bl when your hunter as distance, pala is in cc, and after bubble, shield wall and trinket on pala, and assist nuke on warr. You should also try to purge Sacrifices, Freedoms, BoP, ~(but this should be easy considering you are consistently purging the warrior)~ and FS the warrior whenever he is out of trap / wing-clip.