When you're painting a doorway, you need to deal with hinges and lock plates. If you don't want to remove the door and hardware, try this:
Cover the entire hinge with painters tape, overlapping onto the surrounding door frame.
Now use a craft knife or utility knife with a sharp blade to cut around the hinge so that the tape covers the hardware but not the framing.
This ensures that the hinge stays clean and you're left with a crisp, clean line. Use this same procedure on locks and strike plates too.
People inevitably touch woodwork when their going in and out of rooms. The oils on your skin are invisible to your eye but not to paint.
Wipe down the woodwork with a damp cloth dipped in white vinegar to dissolve the oils and make sure the surface is ready for paint.
Another tip: Keep your room temperatures steady. Paint will not stick to a surface below 50 degrees and the finish will not be smooth and even if it's above 90 degrees.
If the room you're painting in is closed off, make sure the temperatures stay in the mid 60s to be safe.
Painting prep made easy and it's just that simple!