It is not enough to throw a handwritten timeline at the DJ and say "good luck." That's not how it works. If you want the best possible reception, pay for a reception coordinator. Most venues have one, and if they don't, find one. Please.
Picture it like a football team. The coordinator is the head coach, the DJ is the quarterback and the other vendors (caterer, photographer, videographer) are the rest of the team. The coach calls the play in to the quarterback ("father of the bride is ready, toasts in 5 minutes"), then the DJ relays the play to the guests (and the vendors) "ladies and gentlemen, we will be having toasts in about 5 minutes." Everything goes according to plan. Sure, the quarterback COULD run the offense without the coach, but it would not be nearly as effective.
I've had plenty of weddings where there is no coordinator and I'm expected to "run the show." Sounds simple, right? Hardly. Not only do I have to determine when EVERYBODY (guests, vendors, etc) are ready to "move on" (toasts, cut the cake, etc), I have to relay info to all the vendors. So I have to leave my DJ booth, go find the caterer and ask if they're ready, then track down the photographers to see if they're ready, if there's a videographer I have to find him/her, plus coordinate with the bride and groom and ask if they're ready. All this time music is playing and I'm not at my post. STRESS!!
Another situation that never ever works is "my mom will be the coordinator" or "my best friend is a coordinator." Even if they do it for a living, they will inevitably end up behaving as a guest at your wedding (WHICH THEY SHOULD! THE MOTHER OF THE BRIDE SHOULD NOT BE THE COORDINATOR!) and leave the vendors high and dry.
That's why I charge an additional $200 if you don't have a professional reception coordinator. It is too much stress and responsibility on my end to not be compensated. But please, hire a coordinator.