The first place to start (and the one of utmost importance) is to familiarize yourself with the laws in your state. Do research and find out where, when, how and why you can carry within your state. Find out which other states honor reciprocity of yours and consider any travel needs. Ponder over your personal situation (are there children in the house of age to find and misuse a firearm?) and make all decisions responsibly and accordingly.
Once the final decision has been made to obtain said license, the procedure is actually fairly easy; and while there are no federal laws regarding the issuance of a permit, 49 states have passed laws allowing private citizens to carry certain firearms in certain public spaces. (i.e. many states and certain federally-imposed laws DO typically prohibit carrying in some places, including many Federal properties such as courthouses, prisons, and airports, school districts, national parks, etc…). The laws regarding this vary greatly from state-to-state and it is necessary to know and familiarize yourself with this information, as the penalties for carrying illegally can be great; however when exercised with caution, carrying can be the difference between life and death.
Obtaining a license, however, is typically fairly easy for the responsible, law-abiding citizen. In most states, it generally includes three different sectors of dedication: an application process that generally includes paying fees and providing references, consenting to a background test, attending classes, and taking (and passing!) a shooting test. Although the strictness with which these four sectors is implicated also varies greatly from state-to-state (i.e. it is much more difficult to obtain a permit in the state of California than a state like, say, Texas), the general procedure remains fairly consistent across the board.
Do research in your city and find a class that fits the bill for you (many public and private shooting ranges and community colleges offer this service at a nominal fee if you hunt for it). Be prepared for the government to scout through your background files and have ideas of reliable sources of personal recommendation for you. And of utmost important, make sure that you have committed yourself to the decision that you are well prepared and mentally, physically, and emotionally equipped enough to be a responsible firearm owner. The decision to “take the law into your own hands” if need be is a big one, and can be an ultimately important one.