I purchased 4 round led rocker switches and need some help wiring them. Which terminals are +/- and which is the output? The back looks like this

I have seen on here somewhere where someone wired the + leads all together and got the power off the same spot. Where is a good place for this? I also have all the - leads wired together and plan to ground them in the same spot, any problems with this?

One other question, for now anyways. When I wire the switched source, can I just run the power wire from the switch to the source? Do I need anything inbetween the switch and source? Thanks in advance for helping with my ignorance.