I've been in this business almost 25 years and started from scratch cold calling. This of course was before the internet and emails, etc. I would have a goal to make a certain amount of calls each week. I would target businesses that needed a sign repainted (this was before vinyl). You'd be surprised how many business owners park in the back of their businesses and never pay attention to their storefront.
Never ask a yes or no question. When it came to deposits I would ask, "Would you rather do a 25% or 50% deposit, and I'll put you at the top of my list to get the sign done." Even a 25% deposit would cover most of my materials, again mostly paint, etc.
In sales you will realize your success rate, say 10%. So for every "No" you get you realize you're getting closer to a sale, statistics don't lie. Don't be too proud to make sales calls. Many business owners appreciate it when you say " My business is to make your business look good".
I recently did a cold call and left a card with a price on the back to repaint a sandblasted redwood sign for a visitor's bureau. I was told several sign companies had called on the phone wanting to quote the job but I was the only one that actually came in to talk face to face. When the customer says something like that it makes you realize how important spending a few minutes each day in sales works.
If your business is in a slump, rethink your attitude toward getting out and "beating the bushes". Some guys would rather weed 1/4" letters all day than make one sales call.