It took me awhile, when I started knitting, to figure out just what blocking means. There are a few (maybe several) terms that knitters use regularly that are not really clear to those who are new to the craft. So, I’m going to try to give a general description of two often-used blocking techniques – wet blocking and steam blocking.
For most sturdy fibers, I like to wet block. Wool is a sturdy fiber (and if it has a little bit of man-made fiber blended in, it’s still sturdy enough). I would also suggest wet blocking linen garments. I’ve read that some people “whap” their linen once soaked … sounds violent to me but I know it does get “softer” when washed a couple of times.
To wet block a garment, you want to immerse the garment completely in cool water mixed with a little bit of wool wash like Eucalan or Soak. Gently lift your garment out of the water and gently squeeze the extra water out. Never (NEVER) wring hand-knit garments. I usually put the garment on a clean bath towel, roll it up and then press gently to get even more water out of the garment. Then lay it flat on a blocking board or a new clean towel on your guest room bed. Or on an infrequently traveled area of wall-to-wall carpet. Gently pull the garment to the right shape and measurements and let it dry. It may take a couple of days.
An alternate method is to steam block. I set my garment on a clean bath towel and with my steam iron set to the steam setting, Pin the garment into the shape/size that you want it to be. I hold the iron over (without touching) the garment and give it a jolt of steam or two or three. The heat and moisture will relax the fibers enough to make it possible to give it a little bit of adjustment. Let it dry completely. (Another way I’ve heard some people steam block is by using a wet (clean) pillow case on top of the garment and putting the iron onto the pillow, pushing the steam button, until the pillow case is dry. This is a gentler method than wet blocking and you should get the same result.
Note: If your garment is made of hand-dyed wool, and the color isn’t “fixed” and you see dye in the water when wet blocking, you can also add a little bit of white vinegar (a cap-full or two) which should help “fix” the dye. If color is bleeding, keep rinsing with cool water until the water runs mostly clear.
The last method that I want to discuss is spritz blocking. If using this method (which is good for any fibers you have doubts about soaking in water or steaming with an iron … in my house that’s alpaca, silk, mohair, cashmere and anything I’m not sure of … I pin it into shape and then spritz it with a plant sprayer. Make sure the sprayer is clean (hasn’t been used for cleaning chemicals or anything) and filled with water and just spritz the garment until it’s moderately damp. Leave it there until it’s dry.
There you have it. A primer, if you will, on blocking. I hope this helps!