how do i switch my auto insurance policy before my term is up?

lady gaga says:

You call or write your current agent and ask to cancel the policy on the date you want. (You may have to do this in writing; many companies won't accept a spoken request, for their protection and yours.) Make sure it's the same date that the new one starts so there's no gap. You may be penailzed a bit on the return premium, as many companies "short rate" the return (give back slightly less than the full due), just to discourage this sort of thing, so be sure the difference is enough to justify that–if it happens; it may not. If it's a six-month policy, and you're just at the beginning, the difference may be slightly more–2-5 percent.