How to match unlabelled wool.

[Kione]

I am taking up crochet again, and I would like to make a funky jumper with different stitches and colours. I would like to use second hand wool that I have at home and from second hand shops.
I tried this on a tapestry but due to the different thickness of the wool it got wonky, and not flat.

I have checked online and there is a trick using wraps around a needle, but some of my wool goes flat on the needle taking more space than other that when crocheted actually match so I guess that trick didn't work?

Any way of doing this?

Thanks!

The wraps per needle is fairly accurate. Is it going flat because you’re pulling it too tight?

I don't think so, it's the type of yarn I think. Maybe I can twist it with my fingers first to keep it more together.

l still think the wraps thing will work even if it’s flat. That’s how it will behave when it’s knitted or crocheted.

Make a swatch with each wool to get the gauge you want and then swap hook size as appropriate.

I think there’s a bit of skill in using the wraps method. Keep practising.

Thanks for the replies! Yes I will make swatches, didn't think of this.