Increasing my business chances for a line of credit or loan

Now most of you guys know me for asking a lot of questions. How can I up my chances of getting a bank loan or line of credit. I have 3 credit cards that I use. I have a credit union one a discover one and a commercial one locally. Do I need to have my business fully registered to do this, do I need to have paper work that shows my expenses and profit. If so how can I show that. I am new and I have no experience on how to obtain this feature.

Another question that may be irrelevant is with those credit cards with a business transaction such as travel gas and etc are those tax write offs once my business is fully registered as an LLC or does it count now.