There are certain rules that all DJs (should) live by, and it's if they follow these that truly show if they know what they're doing.
Of course, we don't mean the ones that go without saying, like the ability to effectively speak on a microphone, or knowing all your music. We refer to the unspoken policies all DJs should, in our humble opinion, follow, to make it a successful event.
(Note: There are always exceptions, of course, per a client's wishes.) But otherwise, these are some tried and true DJisms to stick by:
1. Thou shalt not dress like you're playing music in your basement; your attire reflects your attitude and professionalism.
2, Thou shalt not play two songs by the same artist in a row. (Exception: A rare medley may be allowed.)
3. Thou shalt not end a wedding on a sad song.
4. Thou shalt not play all the big hits at the very beginning of an event.
5. Thou shalt not talk over the music, but if one does, he/she must hit the posts (the part at the beginning of the song right up until the singing begins).
6. Thou shalt not overplay a song; fade the song/transition out of the song when the crowd has had enough of it.
7. Thou shalt not fade/transition out of a song if the crowd is enjoying it merely because the DJ is tired of it.
8. Thou shalt not act like a jerk if a guest requests a bad song or wants to talk with you; you're a party DJ, not a security guard at the White House.
9. Thou shalt not play a second request by someone if he/she did not dance to the first request he/she made.
10. Thou shalt not make the event about the DJ.
With these commandments securely in place, clients will end up with the right DJ!