Find yarn - and find out what to do with yarn!
Let's start by asking a question that I have all too often: what should I make with this yarn that I already have? (It sounds silly, but I know you knitters feel me on this one.) I encountered this situation recently when I decided I'd had enough with the four balls of Reynolds Whiskey that I bought three years ago. Two balls in midnight blue and two in mango orange. The colors are perfect together, but they turned out not to be appropriate for the project I had originally envisioned for them.
If you go to the Yarns tab at the top of every Ravelry page, you can search by the name of your yarn. If I type in "Reynolds Whiskey" I can click through to the Ravelry page for that yarn. This page provides some information on the yarn - its yardage, fiber content, and suggested needle size.
(Let me stop here and point out that this is invaluable information. If you ever use the yarn ball band but you remember what kind of yarn it is, you can look up this info on Ravelry.)
Now let's explore the tabs on this page! The photos are pretty, but you can do something neat on the next tab, "Stashes." In this case there are currently 832 balls of Whiskey stashed on Ravelry.
Do you need one more ball to complete your project? This is where you look.
On the Status tab, select "Will trade or sell." Then do some searching on your color. Not everyone is good about using the same terms when they stash their yarn, so you might have to fiddle to find the yarn you're looking for. If someone has it for trade or sell, just send them a message explaining your plight. You would be surprised how many knitters will happily trade or swap you a yarn you need!
Now the meat of it: the Pattern ideas and Projects tab. I prefer Projects, because I can see the results, and it has people's notes. You can click to filter the results and show only the projects that have been Favorited, which works pretty well to sort up the good stuff.
This is how I discovered that several people had made the Brooklyn Tweed pattern "Koolhaas" by holding Whiskey double. Perfect! And that is what I shall do, as well.
Thanks again, Ravelry!