Whilst hours are important, it's Johnny on the spot that gets the job. If you are unemployed and can be there to start tomorrow and have roughly the right hours as the next guy you have much more chance. Those that already have a job and write stuff like "I can start with 2 weeks notice" or "I live in PNG but want a job back in OZ" will struggle I'm afraid unless they have a very specific skill / rating / endorsement that the employer requires.
In summary, make yourself available at extremely short notice to be able to be there the next day, don't go saying how you might be able to get a day off from Coles sometime next week, it won't fly and nor will you.