Thanks for your advice. Oh so it is the opposite, should choose the non- red ones. Err the crab no need to clean the inside before cooking?
If you are cooking the normal crab (I mean not the flower crab) its best for your to remove gills first. Ok step one open this part your hands as shown and just pry off and throw away.
Secondly remove the top shell by prying open like this
The remove the gills can be under running water
Ok you are now good to go and do whatever you want to do to the crab.
Oh I forgot to add, for flower crab (pu-ma) if you are purly steaming it, just wash the exterior and steam it no need to remove gills but if you want to make chilli crab or fry it please follow the above steps.
Or I almost forget, how to kill a crab? Errrr this one is easy, just throw it into you freezer after buying it for 1hr, it will not grab you with the pincers after that.