Step 5 and step 7?

Exactly as the title says, I need help with step 5 and step 7. I'm still pretty green with GIMP.

I'm not really sure exactly what they are saying in step 5. Probably the "Levels" tool under "Colors".
Step 7: Click on the "Colors" menu, Select "Threshold" and play around with the settings.

Thanks, I figured it out already though. I had a plane trip and just browsed until I found what I needed/what worked.