I'm not sure what that lighter top layer is...the layer that is on top of the beer (the dark layer), that is.
Either way, you want to wash that bottom layer to separate the yeast from the trub. Looking at the bottom of that layer, you can see that its sort of greenish-beige and that is yeast mixed in with trub. Looking at the top of that layer, you can see its mostly yeast and is more beige/white in color.
1. pour that beer layer off (I'd probably pour that weird top layer too).
2. Add some boiled/cooled water to the bottom layer, mix it up, and let it sit 20 minutes...the trub will settle, but not the yeast.
3. Pour off the water (which will still have yeast floating in it) into a fresh container
4. Let the yeast settle again (overnight)
5. Repeat step 2 by pouring off the now-cleared water and wash with some more boiled/cooled water. There you have your washed yeast.