If your talking about this part :
[...
Remove Excess NaOH, Salts, Etc.
After most of the precipitate has settled, siphon off the cloudy liquid. Reserve this liquid for an overnight settling.
Add about 200ml water to the precipitate, stir, and allow to settle again. Remove and reserve liquid. Repeat this step one more time.
...]
Just keep the liquid you'd normaly discard to let it settle (1 night IE) to be sure to grab any sediment left in it.
[...
Remove Excess NaOH, Salts, Etc.
After most of the precipitate has settled, siphon off the cloudy liquid. Reserve this liquid for an overnight settling.
Add about 200ml water to the precipitate, stir, and allow to settle again. Remove and reserve liquid. Repeat this step one more time.
...]
Just keep the liquid you'd normaly discard to let it settle (1 night IE) to be sure to grab any sediment left in it.