I saw something similar in some pictures that I was looking at for ideas. They put something like this on their wall and lifted the idea - more or less. I used some random fonts and cut it with SCAL using my Cricut. This was my first vinyl cut with my Cricut. It was AWESOME! I will be doing more. It went on easy-peasy. I have some suggestions to you, though. You will need some sort of transfer medium. I used delicate surface masking tape for this one. I like cutting all the way through the vinyl. Then, I arrange it onto the masking tape. I pull off the vinyl backing and put it on the wall, masking tape and all. Then gently pull the masking tape off of the vinyl letters and it is in place. I put this one in the play room. My son is posing by it climbing on top of the slide.
Edit: I have no idea why this photo is so blurry. I took a quick closeup for you.