It wasn't hard to paint this pattern (although it looks pretty difficult). Once we found the pattern on the internet that we liked, we printed it on a transparency, then used an overhead projector to shine the pattern onto the wall. ((The rest of the room hadn't been redone at this point, that's why the walls are still brown with pink curtains...so ignore that.))
Once the transparency was shining on the wall (you can see a little bit on it in the bottom left corner of the above picture), I traced the pattern, moved the projection, traced the pattern, moved the projection, traced the pattern......(I think you get the picture). It was a long process! But I did that until I had the pattern traced on the whole wall.
After I had traced the whole wall, I went back through and painted in the pattern using black acrylic paint. Acrylic paint seemed easier to use because it was a little thicker than regular wall paint. We left a strip in the middle because she wanted her name on the wall, so we decided to use the light blue color of her other walls to paint her name in a black stripe.
Ta-Da! The finished focal wall! Her name was painted in the same way as the pattern. We found a font we liked, printed it on a transparency, and traced it on the wall. Altogether, we were pretty satisfied with how everything turned out, and it definitely ended up being a WOW wall, just like we wanted!