Specialty tools designed to paint edges without needing tape can speed up the cutting-in process for some users.

Purchase paint edger tools (often a pad with small wheels or guides).
Load the pad with paint carefully, avoiding getting paint on the wheels/guides.
Run the edger tool smoothly along the ceiling line, trim, or corners. The guides help keep the paint off the adjacent surface.
Note: These tools require some practice to use effectively and may not always produce as crisp a line as careful taping and brushing. Clean the guides frequently.

N/A - Offers an alternative to traditional cutting-in with a brush, potentially faster but requires skill.

Use Paint Edgers or Pads