The Natural Philosopher wrote:

Mmm. I would steer clear of wood altogether.

We had a Ply sign up for several years and only changed it when the shop
created enough money and our Logo changed.

the sign was cut in 2 peices from a sheet of 18mm marine ply IIRC.

Painted with regular silk vynal paint as used inside the shop then the
logo and letters were up-scaled and printed in reverse on A4 sheets on
an inkjet printer.
Pages were then turned face-side down on the board and traced through
leaving an outline of letters the right way round on the board for
filing in.

Whole lot was then given several coats of a clear varnish (might have
been marine or floor grade whichever was the clearest)

Job done.

Then we had a foamex/vynal board/letters which faded quickly and was a
bit crap all round but lasted for another 3 years or more until we
forked out for acrylic sign with light-box.

Quality of sign depends on funds avasilable at the time, but even a
basic ply sign will get the message across well.

Our Logo and sign design has changed significantly with each version so
no point forkig out big money for a fancy sign in the first years of
business when for a new business it will alomost certainly need revision
and re-design as the business evolves.

IMHO

Current sign reflects the fact that we are a significant entity on the
interweb these days. (top left image) http://www.gymratz.co.uk

Cheers
Pete