It sounds like you're referring to a fictional character, perhaps from a game or book.
To find out how to summon him (if possible), you'll need to provide more information about:
* Where does he come from? What game, book, or other media is he a part of?
* What are his abilities? Does he have any specific summoning rituals or requirements?
Once you tell me more about Gilfred, I can help you figure out how to "summon" him (in the context of the story he belongs to).
For example, if you are referring to a character in a fantasy video game, I might be able to help you locate a specific spell or item that is needed to summon him.