This is a simple knit, based on the “Knit-Twist Lattice Stitch” from Barbara G. Walker’s 
A Second Treasury of Knitting Patterns. As the book says, “…this pattern makes a fine, sharp, clean lattice design on a knit-stitch ground.”

The finished blanket can be as big as you like. Sample is 23” x 30”, but you can easily make any size square or rectangle by changing your yarn weight, needle size and/or stitch count.

You have total flexibility on gauge here. It will be based on your yarn weight and needle size. Sample gauge is about 22 stitches = 10cm.

Use a soft, cozy yarn. Sample was knit with one skein of Loops & Threads Baby Delight, an easy-care DK-weight option for a donated baby blanket. I see that this has been discontinued, but any nice DK weight will work. (You could also use a different yarn weight for this design, adjusting stitch count as necessary for finer or heavier yarns.)

You will need a circular needle of the appropriate size for your yarn and a tapestry needle for working in ends.