• Do not provide personal contact details or any other personal information until you have corresponded via the site a few times.
• Phone the person before you meet.
• Meet in a public place, possibly accompanied, and let someone else know where you are going and when you expect to be back.
• Use your common sense and your intuition. If you do not feel comfortable about meeting in person when it comes to it, then follow your instincts - don't.
• Consider meeting up as part of a group.
Arranging to travel with people you've never met can be a risk; check them out thoroughly before your journey e.g. meet up beforehand in a public place (to vet), check passport, take their picture, let friends know your arrangements etc.
Also looking for a travel companion in the internet can be risky. This is why you should be cautious about finding travel companions this way, but safety problems appear rather occasionally. Many travel sites enable comments so if you have any substantiated objections, you should public them. Some of the sites require an accepted membership – they are based on credit card verifications, personal references, personal vouching systems. So if you are trying to find a travel companion online, you always should remember about your safety!
So if you would like to find someone to travel with, a good travel companion, then you should really think about registering on sites that enable searching for mates or couchsurfing sites. If you will like to spend less on holidays, meet new people, see new places – find travel companions and have fun with them! When you have access to the web you can do it right now – register on selected sites, create your own profile and write about your dream trips – for sure you will find someone similar like you with whom you could travel!