게 꾸미다

decorate it nicely, or otherwise

꾸미다 is decorating or doing up a space, and 예쁘게 꾸미다 "make it look pretty" fills four of these lines. The passive 꾸며져 있다 describes the finished result — 예쁘게 꾸며져 있고 "it's all beautifully decorated", 오늘 이렇게 꾸며져 있어서 "the way the set is done up today". 꾸며 놓다 adds the sense of having set it up and left it that way. The same verb covers doing yourself up, and, in a different sense, making a story up.