If he is bringing live crawfish, really the only way to cook them is by boiling. Adding in corn, new potatoes, and maybe some good sausage to the boil is a must. Seasoning is the key. Most of the pre-bought ones contain flavorings and such....so if you want to make your own it will take some research. Crawfish are a blast to eat. Just like crabs, set up some tables outside lined with newspaper, a big cooler of adult refreshing beverages and water. Spread the crawfish out on the newspaper and go to town. We keep ours in a cooler after cooking so they stay hot, and bring them out in batches.
You might have to rent a big stock pot and outdoor gas burner if you don't already have one......that is really the only way to cook them.
Sigh. I lived in Louisiana for two years, and my husband is from there. We JUST got back from a mini reunion and we did a crawfish night....oh, so so good.
Crawfish is probably the name he would use.....growing up in colorado we called them crayfish, but if you are from the south it is usually crawfish.