Calming oneself down before playing the silk strings on guqin

Last night, I asked my daughters (aged 4 and 7 years old) to close their eyes and place their hands gently on the silk strings to calm their hyperactive selves down for a few moments before they start to freely explore silk string tones on the guqin. I showed each of them very briefly how to play harmonics and how to slide the left thumb between hui positions on the fingerboard. 

After that I left them alone to play totally unsupervised. They are not learning any tunes or techniques yet. Just free and easy explorations. I would just like them to get used to the smooth texture of these Tobaya brand silk strings. No need to rush to teach them any tunes. They gotta develop a love for this musical instrument first. It's the first musical instrument which I have encountered where a child can freely express herself (and sound very good) without any formal training at all, probably because all its 7 strings are tuned/harmonized according to the pentatonic scale. Haha ^_^