A good start would be not to refer to 'Flight Attendants' in the UK cabin Crew is the term used.
Travel industry courses are a waste of time.
You need to understand the principles of customer service and ensure that you research the airline you are applying to.
Dress appropriately if you get an invitation to interview.
Don't say you want to travel the world and meet people!
If you are put into a team situation at interview don't under any circumstances hog the lime light and push the other candidates out.
Get some background in service. Go work for a pub, bar, coffee shop etc. first aid, nursing experience is also a good route in.
Understand the work is NOT glamourous! It is hard tiring and disruptive to a stable home life. Be prepared to spend long nights out of bed and then struggle to sleep during the day.
It can be rewarding in both travel and financial if you are in the right airline so chose carefully.
And oh....good luck!