It depends what you mean exactly by visible paint lines. If you mean brush lines, use a brush to cut in the edges making sure that you have enough paint on the brush, then use a roller to paint the main body of the wall making sure to bring the roller as close the edge that you previously cut in. Brush lines also are caused from over brushing. Can be from too much pressure on the brush, use a lighter touch.
Visible paint lines also come from not keeping a wet edge. Meaning that as you paint you should be painting a section then moving on to the next section before the paint you just painted dries. This is not critical with flat or matte paint, but is absolutely necessary when using semi-gloss or gloss paints.
Visible paint lines also come from not keeping a wet edge. Meaning that as you paint you should be painting a section then moving on to the next section before the paint you just painted dries. This is not critical with flat or matte paint, but is absolutely necessary when using semi-gloss or gloss paints.
