Specimen One...

A simple cross stitch pattern, and yes; it's free : )
The design itself has only 2 colours, but you could use more if you like.
It's also highly customisable as far as size goes, it's fairly easy to make the pattern bigger to fit your needs. This pattern never officially left the drawing board, so I can't really say what type of embroidery linen would be best. As long as the thread you plan to use suits the linen the sky's the limit really...

free cross stitch pattern
The same pattern twice, but with reversed colours (the green is just background)

free cross stitch pattern
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