I print on A4 and gilloutine (just a knit blade running on a special ruler). I use High qual paper and print both sides.
practice on thin paper and hold up to light.
I get two per in portrait. fold to get about 60% overlap rather than 100%. Once you have the thing set-up in Word (or whatever) with boxes you re-use the format for many designs. Hint dont try to get the boxes printing to the edges, design so that the open boxes are a feature.
Enjoy