Thanks Georgie.
I am just at the Thinking out loud phases.
I use a very old program called: PhotoImpact 6.0 by ULead, but you could use many photo and rendering digital drawing tools.
The version I have is very dated, but it's like an old glove
I believe I paid (some where around) $30 back in 2000, and it's still relevant today.
These days, with a digital camera, and photo editing capabilities, you can learn to do so much more than my Chuck-covered wagon program...