Ways to create a wiring schematic / diagram ?

[cruikshank]

Wondering about ways to create / edit / play with a wiring diagram other than pencil and paper.  I'm trying to figure out wiring on a rather large layout with 7 or more loops, blocks, crossovers etc.  I'm using Gargraves so there will be the usual hot and gnd plus a third control wire for possible future use.  Thanks, Dave