My technique is similar to ablrbrau's, but as long as level 3 is homogenous, that's what I really want. Level 1 has yeast in suspension, level 2 is a mystery, and level 3 looks like yeast that has settled out of suspension. Level 3 is good to save because you are getting the most flocculant yeast.
Here's what I would do with your jar:
Refrigerate it for a few days and see if there is any change. If you still have three distinct layers, pour off the first two, and make a starter with the third. Let the starter go for a day or two, then refrigerate it to let the yeast settle. Save the results.