Get some impartial advice from your accountant before you consult the bank. A bank will want to see a strong business plan. Consider raising equity finance (sharing the risk and rewards by selling shares in the business) but if you go down this route be prepared to grant outside shareholders a stake in the business.
Think through the alternatives to getting more finance. For instance, you might have assets against which finance could be raised, such as factoring debtors. Maybe you could manage the stocks and debtors better to free up cash? A hard look at the cash flow can pay dividends.
Could you release cash from underperforming assets? Reduce costs in general? Look also at improving the profitability of your products or services to generate more cash. If none of the above is enough and there is still a gaping hole in the finances, make sure there is a strong business plan to present to the bank