OK, so you've let the egg sit out over night, and now you're ready to go on to the next step. There should be a bunch of clear liquid in the bottom of the bowl, and maybe some stiff bubbles floating on the top
So, now we need to strain it. Take a piece of fine linen and wrap it round the bowl so that you can pour through it.
Once that's done, it's glair. decant it from the bowl into a covered bottle, stick it in the fridge. Add pigments and it becomes paint. Add gold powder and it becomes shell gold. There are a number of uses for glair.