Different colour icing ....

[herethereeverywhere]

I am making a cake with the Irish flag on it. Any ideas on how to do this ?! I am not very good at getting straight lines with an piping back and don't want it to look rubbish! Any ideas greatly received !

Can you buy ready made coloured royal icing and make the flag out of that? I always cheat and buy the ready made stuff as I can't face making it!

I use food colouring to paint on the colours on to ready rolled icing

Ready made seems to be the way to go! Thanks for the replies