Hoods are a useful addition to any costume. (The possible exception to this is if your cloak has a hood on it already.) Not only can they look good but they are great in cold weather and a real god send if it starts raining.
The snood can't really be called a hood. It is simply a tube of fabric that fits around the face and covers the head and neck. It's probably not that suitable for any character except peasants but is a really useful addition to monster kit as it can be used with half face masks to cover the hair and neck.
This is a simple pattern that can be used to make a fairly normal hood. Simply sew the two halves of the hood together and then sew them onto the shoulder section. To make the hood a bit more elaborate the edge of the shoulder piece can be given a frilled edge or decorated.
Any cloak pattern which has a hood can be used to make a hood. Simply make the cloak up as normal but make the body section of the cloak very short.