What happens next in this paragraph?

How to clean enamel paint
Dust painted walls at least once every year.
Dust removal is important for maintaining enamel-painted surfaces, but an annual dusting is all that most walls need. Run the brush attachment on your vacuum over the walls and ceilings to quickly remove dust from the surface.
Options are: a. Vacuuming walls regularly is a good idea so you can focus the sweeping power of the vacuum on the paint and scaling. Remove all dust periodically and spray your paint, or vacuum overnight if that's allowed.; b. Use only 1-2 passes on the brush and no time getting it under the nails. You can brush once a week if you want, but if you don't want to spend extra time dusting, then don't.; c. Always vacuum walls well before washing and cleaning them to prevent scratching. Take the dust out and fill your vacuum's tray with 100ml of water.; d. For smaller areas, a hand duster should suffice. Always dust before you do a deeper clean.;
d.