Look,I'm not the first person in the world to make a jam jar cover but here is a tutorial if you want an idea of shaping and sizes. You obviously have to adjust the 'pattern' to fit your jam jar shape. (UK crochet terms used)
I used a 3.5mm Hook and fine DK yarns all with a bit of shimmer. You can make a chunkier version, just adjust your hook size to your yarn and measure as you go.
Ch 37 as a foundation row
Ch3, skip first 5 chains, 3tr in the fifth ch, *Ch1, miss 2 ch, 3tr* repeat to end. 1tr in the last ch. Turn.
(Doing a ch1 between each cluster makes the work bulge out from the foundation row to accomodate the blow out on the bottom of most jars)
Change colour. Ch3, miss first tr space, 3tr in the next space and every space to the end. 1 tr in the last space.Turn. (there is not a ch1 between each now because we want the work to nip in a bit for the straight bit of the jar)
You can see how the work blows out at the bottom as you make the second row.
Change colour. Ch 3, 1 tr in the first space, 3 tr in the spaces to the end. (you will need to judge whether you need 1tr or 3tr in the last space but essentially you need to keep the sides straight so use either 1tr or 3tr )
And so on... keep changing colours and working rows of 3tr in each space until you reach the top of your jar. my Peanut butter jar needed 8 rows in this fine Dk yarn for example.
Change colour. Ch1, make a row of dc missing some stitiches to nip the work in for the neck of the jar. I skipped a stitch on each cluster and it starts to curl the top of the work in. Work 1 more row of dc in the row you have just made.
So your crochet part is finished, it has some ends to tidy up and it should be curled in at the top and bottom like your jar hopefully.
Sew in ends and sew up side seam. This looks unusual but the tight neck will stop in slipping down.
Hooray!Now you can see why I needed a bit of shimmer, I bought these butterflies in a pound shop in the easter crafts section and thought they would brighten up my 'home corner'.
A crochet jar that matches the colour of my crochet hooks, what could be better than that? Hope yours works out well too. Jo xx
Chunkier version using some Aran and 5mm hook is here.