Have you gotten your case yet?
Cables inside the case will be for Sound (possibly both HD and standard - you would use HD if available), USB 2.0 one connector splits into two USB cables to two ports, USB 3.0 cable (without an adapter, simply bundle up and tuck away) the connector is big and usually blue, there shouldn't be any issues identifying it, you'll get a motherboard speaker with the case (there will likely be no use for that, you can put it away)
looks like that
These are the connectors you are going to be most interested in
In this picture the white wires are the - while the colored ones are the + it's only important for the led's - reset and power switches are momentary switches and don't care about polarity although if specified it should be followed
last pic is my motherboard's front panel header
(purposely you can't read the header labels) You'll notice the right below it there are corresponding markings - those are the header labels and explain which pins are used for what. Most all motherboards include this information printed on them next to the header - it may be a bit offset but it'll be there somewhere - following it you should be able to find homes for all of your connections - USB and Sound, same thing only easier