Applying a painted stripe pattern to the walls can be an effective way to add rhythm, variety, colour and line to a space; however, it can be a little trickier to do than it seems. Here's some tips I have learned when it comes to painting stripes:
Using a tape measure, begin at a wall corner for vertical stripes, or floor/ceiling for horizontal stripes. Use a pencil to mark your measurements approximately at your comfortable arm span apart (for me it's bout 3.5ft) along the length of your wall. Be sure to mark the beginning and end close to your wall corner or ceiling/floor.
2) Make Painter's Tape Your New Best Friend:
When painting stripes, using painter's tape is pretty much the only way to go. Typically, I use a standard 1 1/2" green painter's tape, and I like to have lots of it on hand. When opening a new roll, strip off the first 5 feet or so. For whatever reason the first couple feet on a roll tend to split easily, and it can be very frustrating when you're trying to use it. Get rid of it, and get to the good stuff underneath.
3) Get it Straight:
Once you've marked all of your measurements, align your tape as closely as you can to your first corner wall mark, and stick it firmly at the end, allowing a little excess to go around the corner. Use your left hand to press the tape firmly against the wall at your first mark, and use your right hand to pull the tape roll taut to your next mark (which should be an arms' span away). Stick it in place with your thumb and repeat the process as you move down the length of the wall. For best results use one continuous length of tape to cover the length of one wall. When you're finished, use your hand to press the length of tape firmly against the wall and smooth out any air-bubbles, or wrinkles. If you're carrying the stripe around the room, begin on the next wall in the same fashion, but match the beginning of your new piece of tape up to the excess from the previous wall, bringing it as close to your corner mark as possible.
*Use your pencil marks as a guide, not gospel.*
Even if you've made your measurements perfectly your stripes may still not look straight because very few walls are actually perfectly square, and perfectly square lines on an imperfectly square wall will look crooked. Use your pencil marks as an approximate guide of where you want to be with your tape, but look down the length of your tape and trust your eyes as to what's straight. Don't worry if your tape doesn't align perfectly with your mark, but it should be close. Compare your tape line to the corner line of your wall for vertical stripes, or the line against your ceiling/floor for horizontal stripes. Once you've positioned your tape, step back and compare it with the rest of the room. If it is still off, lift it, and try again.
Take your time during this part of the taping stage, it will save your a lot of time and energy trying to correct things later.
4) Get it Crisp:
Expect your tape to bleed somewhat; however, to reduce as much bleeding as possible, firmly run your fingernail or a coin along the to-be-painted edge of your tape, smoothing and squeezing out as much air as possible. It seems like a pain, but you will not regret doing this later.
5) Paint It:
Apply paint (typically 2 coats) within your taped parameters preferably with a roller, but a brush can be used for very narrow stripes.
6) Remove Tape:
When paint is just barely dry to the touch (approx 15-20 mins), remove the tape. Start at the edge, and slowly pull at an angle until all your tape has been removed.
*If you are doing multi-coloured stripes close together, wait 24 hours before taping the next set of stripes. Even though your freshly painted stripes may be dry to the touch, your painter's tape will not stick to it until it is thoroughly dry.*
7) Touch Up:
Despite all of your best efforts to sufficiently smooth out your tape, chances are that you will still end up with some bleeding. Use a narrow, detail paint brush and a steady hand to touch up the edges of your stripes in the worst areas, but don't get too picky. Take a step back; if you don't notice it, don't bother with it!