If you look to the right of this post you'll see several advertising links on what you need to do. I haven't followed any of them but I'm sure they will tell you what qualifications are needed.
With some airlines glamourous looks would be an additional help but most these days are just after basic competence.
Each airline will have their own requirements. You'll often find a 'Careers' link on an airline website. (It's sometimes hidden away at the bottom of the page).
Foreign languages, any medical training including qualified 1st aid, customer service experience and being able to deal with the general public (the majority of who turn into 2 yr olds after walking into an airport terminal!) will all stand you in good stead! Not the glamourous job it used to be so most airlines have"lowered" their acceptance criteria. Rather drive needles in my eyes, but best of luck to you!! x