I can only speak for Model Master Acryl paints. My paint booth and paints are in the garage and in the winter months it is very cold in there.
To warm up the paint. I take the paints inside the house and I put the paint jars in a plastic bag and dunk them in very hot tap water. I leave them in there until the water itself is room temperature. I then stir the paint with a paint mixer (not shake), the paint is nice and thin and it sprays really nice with no issue.
I too would like to see what others do.