The best thing you can do is be different from the next person. Look at it like this, you are the promoter & you have got 20 demo's to listen to, you want yours to stand out. As someone has allready suggested dont fill the set full of anthems that everybody knows, develop your own style & build the cd nicely. Baring in mind that if you do play anywhere you will more likely play an early set or warm up ( I know When i started to play out I played mostly warm ups untill i got a little name for myself ) so dont bang it right out on your first few tunes, If they know you are versatile you are more likely to get booked.
Also make the cd artwork eye catching sometimes this can make you look more professional.
I not calming to know everything but its just a few things that have helped me get to play at places like the country club & Enzos, hope it helps m8