My first attempt at yeast washing
 

I took some pictures, but this website is trying to extort money out of an already broke college student.

I followed the standard procedure, I collected all the gunk at the bottom of the bucket and put it in a gallon apple juice jug.
I let that sit at room temp for a while then poured the liquid into three jars.
The jars sat in the fridge until I saw two layers form, I poured the top layer into more jars and put them in the fridge until everything settled out.
I then took the liquid off the top and replaced it with clean water.

But today there is a still a distinct layer of lighter material on top of darker material, and theres a lot more dark material.
Is this mostly trub that I have? Where could I have gone wrong?

Sounds like you still have some trub; sometimes it takes more than three cycles to get everything. Just swirl to get the yeast back into suspension and pour into a new vessel.

It doesn't sound like you did anything wrong. Take the top layer off again, bottle it and label it. It should be fine, imho.

Excellent, thanks for the help. I hope to get many generations in my years to come.

I suddenly wonder, why is it important to separate the trub?

You want to separate the trub in order to avoid off-flavors/unexpected fermentation results in the next beer you pitch the yeast to.

Jaded is exactly right. Plus, I made the mistake of leaving too much trub when I bottled. I opened those bottles to use the year a month or so later, and it was like a slop cannon. It was a disaster - shot stuff all over my kitchen.

I learned my lesson from that one. I typicaly wash 4+ times.