Do not iron.

I would iron, carefully. Warm iron, damp teatowel

and avoid the rib.

Or maybe put on a hanger and hang near the shower.

I would probably try it in the tumble dryer with a damp cloth in beside it. Check it every few minutes to see it is all right.

I sometimes use a gentle heat from a hairdryer.

Block it!!

Home-knitted garments look so much better when they've been blocked. Pin it out on a blocking board (you can make one from a piece of insulating foam, an old cot mattress, covered with old sheeting.
Then pin the garment on to it, shaping it nicely.
Cover with wet tea towels and leave to dry.
Or damp the garment first before you pin it out.

It does make an enormous difference.
Some sites recommend using a steam iron over a damp tea towel and pressing lightly, but I think that blocking and allowing it to dry naturally is much better.

sorry, wasn't giving orders
It is just a suggestion

I have never heard of blocking jalima. Can it unshrink woollen items?

Good question silverlining
I could try that with my nice but shrunken cashmere jumper.

Sometimes I've blocked out the pieces of knitting before sewing them together.

This site tells you to soak the item, roll in a towel to remove excess moisture then block:
kelbournewoolens.com/blog/2015/4/tips-tricks-blocking-your-knits

I think I read about it first in a knitting book, can't remember where.

Having ironed a nice knitted hooded jacket I made for GD and spoilt it, wouldn’t do again. Used damp cloth but iron was probably a bit too hot. Try the blocking.

I would pin it out to shape and use a steam iron without letting the weight of the iron rest on the garment. Hold the iron just above it briefly. If you press down, the knitting will get squashed flat and flattened. The steam without the pressure makes it look neater without the flattening. Don't overdo it, or you will never get back the original springiness.

I used the blocking with a damp cloth method on a cardigan I knitted for GS, and it does work. I would try and avoid applying heat. As for shrinking sweaters - ruined one expensive one recently ?‍♀️.

I always use a warm iron and a damp tea cloth.

Block it. That is, dampen it then pin it out to its proper shape and size on a flat surface, and let it dry.

DD, who's a pro at this, uses foam mats that fit together like jigsaw pieces for this process. I've done it on the carpet a few times.

My friend lays her finished garment on a cloth, gets in in shape, covers it with another cloth then puts it under their heavy rug for a few days

Thanks for the tip about blocking. I have done the deed and the garment is resting on a towel in the spare room. I am sure it's going to work. Just got to wait till its dry now. Thanks for the advice! Appreciated.

I hope it works.
It always looks better after blocking for a couple of days until it's completely dry.

I'm knitting something with wool at the moment and it is curling up as I knit!

Yes it did work. It made a big difference to the appearance of the garment. It looks smoother, stitches more even. Very pleased with the effect. Will have to spread it on a towel each time irs washed, but that's fine by me. Thanks for such helpful advice.

Never use steam on acrylic mixes!
It'll go floppy and never get back to how it should be.
Lay flat when damp and let it dry naturally. Mum swore by putting a garment (especially baby things)
between two towels and under the rug!

Was your mum Scottish mcem? My friend whom I mentioned in my post above who does that is Scottish. I'd never heard of it before she told me.

I'm glad it worked mrsmopp and hope your DH is pleased with it.

Yes she was jalima and the advice was passed on by her equally Scottish mum. Gran did this with the many wool garments she made, although the damp cloth method does work with wool. When acrylic and other synthetics appeared she quickly discovered that they were damaged by steam.
I often knit 2 ply shawls and would never use steam. They need to be gently stretched, pinned and left to try naturally.