I want to make a on off switch between my 9v battery and some led's connected to a 6 pin footswitch.

I have them wired like so which the guy at the electronics shop told me it should work.

But the thing is is that the leds come on very dimmly, then the battery gets really hot so im not sure whats going on.

They work fine when connected straight to supply but through my footswitch its like its blowing up the battery.

How do I wire this correctly?
If I'm correctly interpreting that thing that's supposed to represent the switch (honestly, some more detail would have been great), then in one position the switch will short out the battery (which will cause it to overheat and possibly explode) and in the other position would short across the LEDs (preventing them from lighting) while also disconnecting the negative wire from the battery (also preventing the LEDs from lighting). As for why they are lighting at all, I have no idea unless I'm missing something.

If that's actually how the guy told you to wire it (and not a wiring error on your part), you should probably never listen to him again.

How about a pic?
sorry my diagram was a bit poor. hopefully this is better

I thought it was shorting it out but being told to wire it like that seemed like maybe i messed up somehow.

How would the correct wiring be for this to act as an on/off switch?

seems so simple but im missing it
Yeah, that's how I interpreted the drawing (always best to make sure). This is how you'd want to wire it.

The switch in the above picture basically has 2 sides that are independent from each other. The middle lug is the common lug to its side and the outer lugs of that side are the possible connections to the middle lug, depending on when you hit the button. The common lug is called a pole and the possible connections to it are called throws. Hence the name for this switch: DPDT or double-pole, double-throw. You can use either "middle" (pole) lug and either "outer" (throw) lug on the same side, and it doesn't really matter which wire goes to the pole or throw (in this case) because you are only using the switch as a single-pole, single-throw (SPST) switch.

The picture below explains it graphically. It shows a 3-pole switch that looks different from yours but the principle is exactly the same.