This is a pretty straightforward advice, but one that should be noted as I’ve heard of plenty of people that put their heated socks in the washing machine and end up ruining them. Never wash your electric heated socks in a washing machine!
Instead, you need to hand-wash them carefully to make sure the wiring doesn’t get damaged in any way. Most heated socks are pretty durable but a machine wash can easily ruin them so make sure you always wash them manually. Rinse them slowly and wring them as tightly as you can, and make sure you don’t damage anything.
As mentioned electronic socks aren’t very delicate but taking good care of them will make sure they don’t get ruined very soon. When drying them simply lay them out flat somewhere, and make sure they don’t come into contact with pets or direct heat. If you need to dry them faster place them in front of a fan.
This will ensure your socks last as long as possible.