Document the evidence:

Apart from getting help from your co-workers, you should track the failures of your boss. You can find chase the time report, travel report, or expense reports to trap him. Before trying to trap him, you must keep a neat track in your workplace as your boss can turn against you if he knows. More than that, if you are not a best employee, your voice against your boss cannot make any sense in front of your management. Collecting some factual evidence about your manager's flaws will help you to convince them. However, your mission is not to track what your managers do but to do your work as well.

Approach the Right Person:

When you make complaints about your boss, make sure you are approaching the right person who has the authority to take action. In some companies, it is HR department while in some companies HR department may not be efficient to handle this problem. It is sensible to approach the superior of your boss. But if they both are in good terms, your complain will not help you and moreover, you will be committing a career suicide. You need to inform someone who is detached from your boss.