You need thick yarn, some PVA glue and baking paper (or other easily detachable surface to work on).
Cut several 20-30cm pieces of yarn and soak them in diluted PVA glue
(1 part glue to 3 parts water). Use a couple of pieces to make the
desired shape. You can use different-colored yarn. Make sure the pieces
overlap. After you have made the frame, you can fill it in as you wish –
just make sure you stick to your outline.
When you are ready, press the heart well (it’s best to leave a heavy
object on it for a few hours). Leave in a warm place to harden and dry
(it will take a couple of days). When it’s ready, it should be easy to
remove from the baking sheet. Decorate with beads and sequins, if you
wish.
allikas:
http://krokotak.com/2012/11/yarn-hearts/