The steps and time for steaming crabs are as follows:

1. Wash the crabs with a brush.

2. Use cotton thread to tie the legs on all four sides.

3. Add an appropriate amount of water to the pot, add some cooking wine, put the crabs on the steamer, and sprinkle with some shredded ginger.

4. Steam over high heat for 5 minutes and low heat for 10 minutes.

5. Cut the cotton thread and add ginger flavoring when eating.