- 1). Make a mark on the wall with your pencil where you want the first stripe to begin. You may need to use a ruler or measuring tape if you want to start a specific distance -- a foot, for instance -- from an existing fixture or point on the wall.
- 2). Use your ruler to measure out the desired width of the stripe. Make a mark at the point where you want the stripe to stop horizontally. If, for instance, you want a 6-inch wide stripe, make a second mark on the wall exactly six inches from the mark you made in Step 1.
- 3). Place the T-square flush against the wall and the floor so that it lines up vertically with the first mark you made.
- 4). Draw a straight line from the floor to the ceiling using the T-square as a guide rail. If the T-square is not long enough to reach from the floor to the ceiling, flip it over. Place it flush against the wall and the ceiling, line it up with the mark and then continue the line.
- 5). Repeat steps 3 and 4 for the mark you made in step 2. This will result in an outline for your vertical stripe.
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