Because it's a service for the country
Be honest, make sure fitness is at a good level and don't be cocky
Correct attitude and sense of humour.
Know your chosen role and what to expect throughout your career.
Get fit, be yourself
Research about the Forces, what do they actually do.
Preparation in terms physical and mental fitness.
Appearance, the dress code.
Planning your roots to avoid being late.
Practice & preparation is vital
Truthfull open minded and willing to try your hardest.
Get fit, be prepared to be educated, ordered around and make your self a better person. 3-24 years, it doesn't matter just enjoy.