Jobs at Ryanair vary a lot. You may think that it all about cabin crew, but actually there are also sales managers and an administration team that work behind the scenes. Therefore you will need to demonstrate different skills, depending on which role you want to take up.
It is always wise to find out things about the company before you go for an interview. You need to consider who they are and what they do as well as recent news. The head of Ryanair is always in the news with regards to airport tax and things like that and so it is a good idea to be aware of that, just in case you get asked.
It is wise to also know what the job requires. This is because you will be expected to demonstrate that you are able to succeed in the role and therefore need to know what is expected of you. It is very important to think of each of the requirements and see whether you can think of something that you have done which will demonstrate your ability to do that. It may be that you have done a similar job before. If you have not, you may still have something which has skills that you can apply.
Some of the jobs at Ryanair require language skills and so this may be something that you need to demonstrate. If you have not spoken a foreign language for a while then make sure that you practice and also think about the kinds of things you may be asked to say in different languages. Foreign language roles tend to be sales roles and so you will need to consider what will be relevant there.
Having an interest in travel, flying or airplanes can be really useful as well, so consider how you might answer questions that are about this. Depending on what your role is you may have to show an interest in mechanics and airplane engines, flying and what happens during a flight or travel and the joys of flying. It could be useful to know about any recent and relevant travel news as well.