A lot of people here seem to have worked with this method in particular, in my opinion it’s one of the easiest and most effective way of requesting a spirit from an entity, mainly because you’re able to write down the desired traits and specify on the relationship you’re seeking.
If you use the search function a bunch of post describing others experiences in the subject.
This post by @succupedia is probably one of the most informative to read through on the subject.
Hope this is enough to at least get you going in the right direction.