Take a time, anytime that works for you that you can consistently rely on and plan your prospecting efforts.
Use this time to make prospecting calls, follow up with referrals, write your press release, or any other activity that will bring more people in the door.
The best time for me to do this is Monday afternoon.
Monday morning is reserved for following up on pending business and making sure I am on track with those details and Monday afternoon I spend prospecting.
Batch your time and efforts for better output and increased productivity.