How to parallel wire subs when you have 2 terminal cups?

i have 2 single voice coil 4 ohm sub woofers.i want to wire them parallel to get them at 2 ohms but my subwoofer box has 2 terminal cups.i don't know how to wire them parallel because of the 2 terminal cups my sub box has. can someone please help me. if you can please show me a picture or video on how to do it. because the 2 terminal cups on my box really confused me on how to do it.