Make sure you have a business plan, which includes a financial plan. That should be your bible - forever - when you run your business.
Paid advertising helps. Sadly, to get publicity in the major places you need money. So, if your not willing to drop between $100-$1000 a month on advertising don't expect much, your going to have to go to forums and actually compete for clients in the request area or the offers section.
I've seen hosts that have been open for a little over a month actually make profit and expand. These hosts generally go for a specific advertising market, VPS for example is a hot market right now.
Doubt is a huge crutch for any business. If you doubt it is going to work, don't even try.
I've seen people put down new hosts as not reliable as well, and usually for a good reason. People have no reason to lie, 99.99% won't do it randomly or out of spite. There are two (main) reasons people put down hosts: A: You have done something to anger them, which includes lousy service. B: They want to be an --- and just ruin a host.
If you have done something that caused your business to have a negative rep, I would look into that and fix it.
Another major problem when it comes to new hosts is they offer unreal deals. "1TB BANDWIDTH FOR $2 A MONTH!" or even "80TB SPACE AND UNMETERED BANDWIDTH FOR $4 A MONTH!". Nobody is going to take them seriously.
Then comes the customer service. You can't just check up on the place once every two to three days. Doing that will pretty much guarantee you will fail. You need to be there constantly, every single hour that you can be. You have to be on top of things. If you can't do that, hire someone that can.
I hope my advice helps you, although I very much doubt you will listen since I have given you this advice before and you did nothing.
Essentially, if you do all of the above you will get a few clients. But you also need to understand the shared hosting market is saturated to an extreme, and if your not willing to wait one or two years to start breaking even in (some) cases, you should quit while your ahead of yourself.
Usually, a business takes between one to two years to break even, and that is pretty much any business and not just hosting.