Maybe you've seen it before -- set in the everyday scenery of a city, a random bit of knit or crochet fabric where it shouldn't be. Maybe it's covering an object, like a bike, or maybe it's a scene tied to a chain-link fence. Either way, what you've just experienced is yarnbombing, a form of street art that uses fiber to create beautiful pieces that are placed in public.
To make this knitted graffiti, you need the measurements of whatever you're covering and the gauge of the yarn you're going to use. Then you'll make pieces that will fit around the item (likely multiple pieces that will either be sewn together or attached to the item individually). Then you'll tie it up so it doesn't fall down. For the more mural-like creations, you just need to get creative. It's art! It doesn't have to be perfect to be fantastic. There are no exact instructions because each piece is customized and unique.
Plenty of artists have made names for themselves through fiber graffiti. Olek is known for her large scale crochet pieces that cover public objects, like bicycles, a house, and even the Wall Street bull statue. London Kaye makes pieces that more resemble paintings or murals with crochet pieces that hang in various places in cities throughout the world.
The disclaimer, of course, is that guerilla-style yarnbombing that isn't commissioned or approved by someone is generally considered graffiti and therefore illegal. So we recommend participating in a project that has the proper permits and permissions so you're not breaking any of your local laws. We definitely don't want you doing anything illegal! But often groups at schools or community centers will organize approved yarnbombing events to legally beautify an area. Check with local fiber groups or do some online searching to see if anyone in your area is doing something. And if not, see what you can organize! Everywhere will have different rules about permits and public art, so check your local government for that. You can also work on private property if you have permission from the owner. Wherever you're hanging your work, make sure you aren't damaging any plants or animal habitats, and never cover up traffic safety signage.
If you decide not to yarnbomb publicly, you can always create art for your home or to give away as gifts. Smaller, decorative home items can be covered in yarn for a unique DIY touch (if you're yarnbombing a lamp, be careful not to get too close to the bulb for safety reasons). As with public displays, make sure your work is safe for the environment it's in. If you or your recipient has pets or young kids, put the object where they won't chew on it and potentially swallow something dangerous or tangle themselves up in any loose pieces. If you're putting it in a yard, check that you're not damaging any animal habitats or prohibiting plant growth.
Even keeping the legal and ethical questions in mind, you can still have a lot of fun yarnbombing! Be creative, enjoy yourself, and remember, it doesn't have to be perfect!