Advice on how to harmonize piano and guitar?

With playing these 2 different instruments together, what are some essentials to know in order for the instruments to harmonize and not clash? Like, for example, should they play in different octaves? If so, which should be higher and which should be on a lower octave?Advice on how to harmonize piano and guitar?
Its all about writing around scales.





One instrument, say the guitar, could play the same 4 chord pattern. e.g. G, c7, E minor %26amp; D. Then to harmonize, the piano can play any notes in the G scale, an then C7 scale and so on.. following the pattern the guitar is doing.





Using different octaves works great and it would normally be the piano that would go higher. Advice on how to harmonize piano and guitar?
try tunning the guitar to your piano thats what we did