I used rubber "p" clips to hold 1/4" solid aluminium round bar which I could bend to go round obstacles and corners. This way I could route cables almost where I wanted with as many cable ties as I pleased without it looking untidy.
Aluminium round bar only cost me £4.50 for a 4m length.
This made it easy to mock up cable routing just using only a few cable ties to hold in place before covering in split conduit.