Despite some members not liking advice being given (not sure what the forum is for if not for advice) I am going to give some for what many already know, but some are just about to find out.
Jan and Feb are notoriously quiet and whilst you may be patting yourselves on the back after a busy few months on the lead up to xmas, you're going to find it tough between now and March, April or even May.
You need regular work, and if your customers aren't giving it to you, you need to find more of the same, and you need to build up your network of courier co's to try and get what little work there is.
So if the phone is dead, pick it up and breath some life into it... Get some flyers, target an industrial estate... Get out there!
You may think i state the obvious, but as you all know, what's obvious to you and me ain't necessarily to someone else