Coloured noteheads

Hi.

I am a novice MU user. I use it to re-write parts for the euphonium section in a brass band (Bb transposed treble clef - you know the score?)
I would like to be able to colour note heads where a "tutti" part splits into 2 or sometimes 3 parts on the same staff. (I would have the same problem, only worse if I re-wrote the cornet section parts).

I have somehow managed this in the past (to display and print different parts -eg Euph 1 & Euph 2- in different colours) but despite much searching and experimentation cannot replicate the feat.

I hope you can help.

Mark