I have had a few artists who come to me for advice many times on getting signed and building a career for themselves in music. It might sound funny but I always suggest they try out for the x-factor as you simply never know what might happen.
If your singing career hasn't yet taken off then you simply have nothing to lose by going on the x-factor! Just think that even if you don't win the show you will have exposure to millions of people including senior people within the music industry who may well be lining up to try and sign you at the end.
Not only that but just from appearing on the show you will gain a huge fan base which will be about ten times what you currently have!
Just be going on the show you will already gain some followers and people who like your style and so from there it is all about building on that. These days getting followers on Twitter and fans on Facebook can be a great way to keep the fan base growing. So whilst you are on the show make sure to get fans but also to keep them as once you leave its only them that will support you.
On the flipside, if you mess up on the show then it can make your career harder to get off the ground. This is quite rare but its obviously important to know the things you need to avoid doing before you go on the show and make a fool of yourself!