Cattley guavas can be fairly easily propagated by greenwood cuttings, root cuttings, layering, or seed. It sounds like you are trying to do it with cuttings. If you described the process you've been using, we might be able to give you recommendations on changes that could improve your changes.

There are many online sources for propagation instructions. I will pick one, somewhat at random, and post the link below. The instructions they give don't have to be followed exactly (or even very closely), but there is a lot of detail that may give you some good ideas.

Here is a link that might be useful: see 2nd paragraph under PROPAGATION

Thank you Brandon. The link was very helpful..My method is simple, the same that I use for everything. I put cuttings in soil. Sometime I use rooting hormone, sometimes not.