Speed is the key... or rather, the lack of it
When heaving to in a light displacement or fast boat, you need to make sure you have enough way off to be able to stop the boat tacking when you put the helm down. The best way to do this is during the initial tack – just before the jib backs, stay head to wind until you’ve lost most of your way, before bearing away and then lashing the helm. It’s the easiest, most stable way to do so.