Gnuplot tips

Gnuplot "Not so frequently asked questions": Link

Gnuplot colors: Link

Gnuplot line types: Link

Gnuplot point types: Link

P.S.

How to make .eps grayscale:

gs -sOutputFile=grayscale.eps -sDEVICE=pdfwrite \
-sColorConversionStrategy=Gray -dProcessColorModel=/DeviceGray \
-dCompatibilityLevel=1.4 -dNOPAUSE -dBATCH color.eps

(source here)