1. Look around at the journals for the last couple of years and see what other philosophers are talking about.
Make sure you don't look any farther back than 5 years. Remember the concept of philosophy, I'll follow Wikipedia for convenience:
Philosophy is the study of general and fundamental problems concerning matters such as existence, knowledge, values, reason, mind, and language.
And those fundamental, general problems change every five years.
I'm sorry. What I mean to say is that as we inexorably march toward truth on those problems, we solve sub-problems that are steps in the resolution of the overall problems, and every five years or so these subproblems are resolved, leading to new ones as philosophy advances.
2. Pick a topic that (a) you have enough background in that you won't have to start your research from scratch and (b) you can come up with some opinion on that no one else has supported. Don't worry whether your theory makes sense or can be reasonably justified. Just make sure it's new and different.
3. Pick a major philosopher who has written on this topic and summarize his/her recent work. It helps if the author has just published a major book that is under much discussion.
4. Find some earlier, obscure philosopher who wrote on the same or a related topic. Obviously, the more obscure and respected, the better. Wittgenstein works best. This works because Wittgenstein's later philosophy can relate to anything from metaphysics, epistemology, even moral philosophy (with his work on rule following, for example).
5. Interpret your obscure philosopher in a way that supports your position on the topic. This way you can rely on the authority of the esteemed philosopher. So, your actual position doesn't have to be well-supported by argument. Your view is presumed to be reasonable because Big-W said it. Don't worry about making your interpretation plausible either. No one really understands him anyway.
We all know that you can't argue from authority in philosophy. But we do shift the burden of proof to anyone disagreeing with us by appeal to authority. I know this is a distinction without a difference, but just pretend it makes sense that philosophical authority can provide sufficient plausibility for your view that you don't need to argue for it, just to defend it against arguments against it.
6. Show how your position avoids at least one of the recent problems noted with the other, recent philosopher's account. Don't worry if your view is susceptible to other, more serious problems. All you really need is to respond in some way to a contemporary problem so that it looks as though you've advanced the discussion somehow.
7. Tada! Declare victory; you're done. You've now suggested an original, interesting solution to a traditional problem--even though it raises other, possibly much worse, problems. Sure, your interpretation and solution may not really make sense, and probably raises much worse problems than it solves. But that just means you've got the basis for another publication!
(Results may vary. No guarantee of publication implied.)