Okay, heres the best i can describe it.
1. push the tongue as far forward as possible.
2. look where the tongue connects to boot, located the silver part on the tongue
3. the silver part has 2 tongs if you will coming out that stick in to two little holes in the boot
4. pull those two silver parts one then the other out of the holes that they go in to.
bam, you now have separated your tongue out of the boot
dont be gentle, it takes some effort btw