As with most industries, securing some good work experience is definitely time well spent. These can vary massively (both in terms of length and quality), but if you're given the opportunity to do some in-depth work for a fortnight, then it will definitely make a difference to your CV.
If work experience isn't enough for you, then look for the chance to be an intern. The real difference here is that interns often end up being employed at the company if they perform well. No pressure now...
While it might initially seem daunting to introduce yourself to successful businessmen, the wonders of the internet (namely LinkedIn) have now taken away much of that fear. Be friendly and professional, but don't pester them - think about the kind of message that you would be likely to respond to if you were in their position.
Another brilliant opportunity to network is the traditional careers fair. Not only will this let you check out the latest selection of travel jobs, it also gives you the opportunity to speak to recruiters and employers in the industry. Take this chance. There aren't many situations where you're sure that you have an opportunity to impress employers, so don't miss this opening. You can even treat it as a mini job interview - dress smartly, ensure that you make a good first impression and take a real interest in the company.
If you know which type of travel job you want, read up on all the specifics of it so that you know exactly what it entails. Take a look at tourism magazines, career forums, LinkedIn profiles etc, and build up an image in your head of the skills that you would need to be successful in that job and what an employer is looking for. Having a clear idea of what it takes to succeed in a particular job will help you tailor your CV and plan ahead for any potential interview.
Start your own business
Yep, it's scary. But if you really can't convince anyone to give you a travel job, then why not be your own boss? It may be risky, but many, many people have done it successfully in the past and many more will in the future. Don't jump into it, but if you have a unique idea for a business and real determination to make it work.