To post to someone else's board, you have to be invited to be a part of that board. Then you pin just like any of your boards (it will show up on your list).
I get most of my views from pinterest (more than any other source), and I rarely pin my own products. I pin stuff that I would pin to a regular pinterest...things that I want on my pinterest boards. If it is relevent to my etsy, I find a way to put the link at the end of the description. For example, I had a pin that was repinned over 5000 times (it was in the popular section for some time) that was a home decor pin of a beautiful living room. It had a blanket on the ottoman, so I put at the end of the listing "Get blankets for this look here: allieblankets.etsy.com". What was cool about this is a huge majority of the people who repinned it did not change the description, so people that follow them saw the link to my shop as well. Other popular boards of mine are a board of inspirational quotes, a board for the disease I have, and then of course a crocheting board. I get an email with every repin, and if I like the board they repinned to I go and follow the board, which helps me interact with all kinds of people and connect. Once I follow people usually follow back, which is neat too. I truly enjoy pinterest and like the exposure it gets me! Now granted, with pinterest it might not all be people who with actually buy my afghans, because people repin etsy listings all the time to COPY them and make them THEMSELVES, not buy it. So I try and pin my patterns more than my actual blankets since that is the kind of item they are more likely to buy.
