If your blocks and spaces seems to work out wider than they are high (as mine always seem to) print out the chart and turn on its side.  Then proceed to work from bottom to top.  Hope that makes sense.
 
Start with a chain of 151 and work 1st dc in 4th stitch from hook.
 
Stitches:
 
x = block
I  = shadow space:  (ch1, 1dc) twice.
 
If you are new to filet crochet you will find a tutorial on this site.