Case fan wiring

[the_polish_express]

I am putting together my first pc right now and have a quick question. My case fans have a 3 pin plug that goes into the motherboard and it has two other connectors that look like they plug into the psu, which wires do i want to connect? thanks for any help

 

[505090]

mb first, the other thing is an adapter in case you don't have enough fan headers