Finished size for these instructions 7” square/18cm square approx using 25g of eco-stitch yarn. You can make 4 of these with one 100g hank if you stick to the size given (casting on 39 stitches).
If you want to make it bigger, the pattern is a multiple of 8 stitches, so you can add 8, 16, 24 stitches etc. to the cast on stitches, and knit a few more rows until square.