There are lots of patterns you can try with mosaic knitting, Barbara Walker's stitch dictionaries have quite a few mosaic patterns in them.
Mosaic knitting is thick, thanks to the yarn carried behind the slipped stitches. It makes for thick socks. It's easier to do than fair-isle; it does look a little different. It is fun to experiment with it using a mix of knits and purls.
Here's a simple flat-knit neckwarmer to try if you aren't familiar with the technique. It's done fast!
2 colours of DK yarn (I used the 2 ends of 1 skein of slow-striping Lion Brand "Amazing" in mauna loa, so each end had a different colour)
appropriate needles (flat-knitting)
Cast on a multiple of 4 sts (I used 40).
All first stitches slipped PW, all last stitches knit - between these edge stitches execute the following:
row 1 colour A: [K2, sl 2 pw with yarn in back] to end, end with K2
row 2, colour A: [P2, sl 2 pw with yarn in front] to end, end with P2
row 3, colour B: [sl2 pw with yarn in back, P2] to end, end with sl 2
row 4, colour B: [sl2 pw with yarn in front, K2] to end, end with sl2
repeat for a while (4-8 rows). Then, switch to:
row 1, colour A: [sl 2 pw with yarn in back, K2] to end, end with sl2
row 2, colour A: [sl 2 pw with yarn in front, P2] to end, end with sl2
row 3, colour B: [P2, sl2 pw with yarn in back] to end, end with P2
row 4, colour B: [K2, sl2 pw with yarn in front] to end, end with K2
repeat for a while, and switch back to the first pattern. Random switches look best, unless you want a really regular "checkerboard" look.
[close-up of the K2/P2 mosaic pattern
in Amazing, colour mauna loa]