I have just completed my first afgan. :yay: :yay: :yay: Yipee!! What is blocking and how do I do it to a completed project? Help!!!
How do I block an afgan?
Blocking is ironing your project so it looks finished and lies flat. You do this carefully, by first pinning it into the desired shape then using an iron set on Steam - and a wet dish towel [without the nap].
After pinning it, you wet the dish towel, wring it out and place it over whatever part of your item it covers. Then press it with the steaming steam iron, using gentle pressure and lift-press; lift-press type of technique.
When you’ve ironed the whole towel area, if you still need to iron another portion, you re-wet the towel, wring it out, place it over the unironed portion and iron. Repeat until all of your project is pressed.
Now leave your ironed treasure lie as still as possible overnight so it can dry and cool and generally settle into its new forever-shape.
Okay. Now on to your afghan.
Do this same technique. But I would take a CLEAN bedsheet and place it over some towels laid out over your rug. Then you can stick the pins into the towels/rug and have them hold the afghan in shape. If need be, you could fold it in half - but this would result in a crease where the fold is.
Well, hope this helps.
Dot
PS - do be sure not to walk on your new afghan while it’s on the rug. 
PPS -CONGRATS on finishing a whole afghan!!! What pattern did you use?
I offer this site as an option. Dot’s idea of ironing has been around a long time and works well if carefully done, but some stitches don’t like to be ironed and some materials don’t iron well.
What fiber is your afghan made of? If it is acrylic you could still wet block it and it will finish it up a little, but ironing is a little scary. Lucy Neatby gives good directions for the wet blocking, but sometimes I do it in an even more simple way. If the afghan looks pretty good and doesn’t need a lot of help I might just lay it out, spray it and call it good, or pat it a little or lay table knives along the edge to hold it nice and flat if it needs coaxing. It depends on what you want to accomplish.
Look at the site and decide what you need to do. There are even more options you could research.
If the yarn is acrylic or a blend, or superwash wool, all you need to do is machine wash and dry it.
I guess I have to be embarrassed and admit that I do not normally block my afghans unless I’m giving them as a gift. I will start using them right away, because I’m anxious, and at some point they will make their way into the washer and dryer (since I use acrylic yarn for my afghans) and they get ‘blocked’ through use and washing/drying. While certain yarns need to be wet blocked, and don’t tolerate the heat of steaming, if I do steam block things, I have a steaming iron that puts out a nice steady spray of steam, and I pin the item to the board to the measurements, and then hold the steamer 6 or so inches above the item and also mist it at the same time, and then leave it to dry. Or sometimes on smaller items I will wash them in the sink, roll them in a towel to get out the excess moisture, pin to the board and let them dry naturally. It really depends on what the fiber is as to which approach I take. But for me, afghans are like socks in that blocking is usually something reserved for gift giving.